It's simple:
You don't need evidence to support someone
You do need evidence to attack someone for not doing so
and on the other end
You don't need evidence to be skeptical of an accusation
You do need evidence to call the accuser a liar
Frankly speaking, I don't think it's quite that simple at all (though I respect the use of green and red to illustrate your point). While hurling insults like "corporate bootlicker" is unnecessarily hostile at best, I also think it's entirely fair to question the motives behind whether someone vocally supports or vocally doubts an accusation. While there were plenty of folks who were legitimately concerned about the harassment Kamiya and Hale received, how many others were searching every nook and cranny of Taylor's social media to discredit her, including random people she follows on Twitter, just so that they could defend their favorite game developer or feel okay buying and playing Bayonetta 3? Of course, there's a case to be made that some people who supported her already disliked PlatinumGames and never had any intention of playing Bayo 3 anyways and were happy to find another villain in the games industry (God knows there are plenty of them). From my perspective, a lot of folks who claim that they've been attacked were simply disagreed with. The line, I think, is less clear-cut than you're suggesting.
I also question whether being "skeptical" of an accusation is all that far from calling the accuser a liar, at least in practice. In theory, yes, a healthy dose of skepticism towards any situation is a good thing. But when you're spending more time being
skeptical of an accusation than you are supporting it, then you've taken a side, whether that was your intention or not. If all I did was compile a list of every inconsistency in an accusation, loaded it up onto my favorite social media site, and watch it get clicks, I don't
have to suggest that the person is a liar. But in practice, I've added a whole lot of fuel to the fire, and lent credence to the conclusion that they are, in fact, a liar. In this case, my skepticism would be rewarded! And even if their accusations turned out to be true, I could simply argue that I wasn't taking a side at all.
It's a win-win illusion of neutrality that, in practice, largely benefits the accused. The social media mob mentality, meanwhile, benefits the accuser (at least in this case—there are at times, like the Depp trial, where the reverse is true). There is no position of neutrality. That's not necessarily an ideal conclusion, but I think it's important to consider. Or not, that's up to you.