I feel like I have to weigh in on this. I'm a long-time fan of RLM's, watched their videos basically since the beginning, at least of their mainstay shows like Half in the Bag and Best of the Worst. I love their channel and practically everything they do, their brand of humour is definitely aligned with mine. However, I also appreciate that there is a level of detail in their critique (specifically Mike and Jay) that I personally don't see in many comparable YouTube channels (definitely not ones focused around big pop culture phenomena like Star Wars). Like many, I got hooked in through the Star Wars Plinkett reviews - however, looking back, this is probably some of my least favourite content of theirs. I particularly enjoy their Best of the Worst's.
So, I feel like I have a pretty good handle on how these guys operate. They like to make a mockery of Hollywood, mainstream media, online trends in general, it's their shtick. They shine a light on what's going on and for me a lot of the humour is derived from highlighting the illogical nature of certain trends. Take an example - gender representation within film. Ghostbusters 2016 was a particularly incendiary case. What separates them, for me, from a generic group of white males wielding pitchforks somewhere else on YT is they're not criticising the fact of the gender reversal within Ghostbusters 2016, but it's how that's been manipulated by the studio to achieve a particular goal that is NOT in the best interests of women represented in film. They talked about this multiple times in all their Ghostbusters 2016 videos. For me, whilst RLM may engage with particularly tense issues and at a surface-level value, it is immediately perceived as 'Why do these three white men get to have this particularly say on this issue?', they are always using these views to enforce specific comments. In their Annihilation review, they talk about how the film has multiple female leads, all characters with STEM occupations and respecting that fact. This as opposed to a studio like Sony who saw the 'outrage' as an opportunity to make completely unsubstantiated points about women within film and basically treat the subject matter like a joke. Whereas a film like Annhilation, which commercially tanked, is the leading example - something which does it organically, treats its characters with respect and an audience wouldn't bat an eyelid.
This is just one example but for me, this is emblematic of RLM as a whole. They praise female performances and female actors, they praise actors of different ethnicities, they have praised diverse casts (Fast and Furious is an example), they have called out what they perceive as stereotypes (Jay did in Suicide Squad review). From the OP, the Scientist Man video is blatant sarcasm. This is their MO - the real commentary is in their primary Ghostbusters 2016 review, as mentioned above. The Plinkett video is a comment they have made before and actually one I disagree with. They said it about Wonder Woman, why a kid should have Wonder Woman, a fantastical character as a role model, as opposed to real-world successful women such as Marie Curie, for example. I disagree with them about this, for me, there's no harm in children viewing fantasy stars as 'role models'. They promote positivity and diverse representation is a benefit for kids to see because as they grow up, they're more accustomed to varying different types of person not only on screen but in their workplaces and towns. There's just an undoubtable net positive from that. This being said, I don't see this as an 'outrageous' take from them. I do see their point about how diversity IS a force corporate component. It's a long-standing take by Mike, he says something similar in his Phantom Menace review about Sam Jackson. This is a justified comment. Corporations, who do not care who is satisfied by on-screen diversity as long as it lines pockets, are being manipulative BUT Mike seems to fail to understand that, in reality, it does not matter. A black kid sees Sam Jackson on screen being a badass and that's a positive. They are cynical middle-aged men with no children, I'm not entirely sure why they have such a firm grasp on what children do and do not want to see.
Like I said, I've watched these guys for a long-time and Mike and definitely Jay seemed pretty copped on people. I cannot remember something that can even be considered racist or sexist on their Half in the Bag or Best of the Worst's shows within context of what is being said. Whenever something is said, it's hugely mocking a particular director, perhaps of an old-school class or a type of studio mandate which they perceive as being sexist or racist. They have been very open in the past about 'condemning' blatant acts of sexism and racism within certain modern blockbusters. Do I think that they slightly lean into online trends because it's click-worthy? Yes, I do. I do think they are, ironically, part of the problem they mock within The Nerd Crew. Even if it's done as satire. So, I will not completely die on a hill for them. Their Last Jedi review, specifically Rich and Mike, without a doubt played into some of the lazy criticism we'd seen levelled at the film at the time. I do think it was just two Star Wars nerds getting in a fluster about something because they didn't like it, I don't think there was anything sexist about the review though - they criticised Holdo and Rose but specifically the character's actions during the film. However, the recent Captain Marvel film was a bit of a weird one, to me. I think they are definitely buying into things because it's the sort of, flavour of the month, sort of thing. Half of that video was about a controversy of the sorts they have in the past decried people for complaining about. I would perhaps go so far to say it's a character attack on the actor that wasn't particularly justified (they have praised Brie Larson's performances in the past, so it wasn't as a result of that). I can definitely see why, at a surface-level, people may wish to lump them in with other sorts of online nerd right-leaning types on YouTube but...I actually think it's incredibly ignorant to do that.
However, I have held off on commenting on one particular faction and that's Rich. I liked Rich before I saw pre-rec. Multiple times on pre-rec, he would highlight his gross ignorance towards the wider political situation in regards to many, many things. The example in the OP of the Women's March is just one of them. He displays a staggering level of cynicism towards many aspects of life, generally speaking, to be honest. It really put me off him, in those pre-rec videos. Nobody likes a centrist bastard who hasn't even done his research. However, Rich is a small part of RLM and he's been relatively benign within RLM's channel specifically, not pre-rec, in terms of political commentary.
It's difficult to bring together all my thoughts cohesively, especially as I'm kinda knocking this out there quickly, but I just wanted to put forward SOME level of defence for them. I consider myself liberal, I'm left-leaning (supporter of Labour within UK, although it's a bit...difficult in and of itself at the moment) and I don't particularly follow any other comparable types (based on accusations levelled against them in this topic) to RLM on the internet. I'm just speaking as someone who has followed them for a long time and feels like they essentially know the guys and how they operate/feel about particular things. I don't deny they dip into black humour and they toe the line but not everything is as binary as people think in this world and I'm just staking the claim that RLM are, at the very least, within the moral grey.