Okay, so I'm going to make the assumption that you are asking this in good faith, and am going to try and explain it to you as best I can.
First, despite your or that poster's apathy or personal anecdotes, representation and its quality matters. This should not be shocking, video games are just one of many commercial storytelling mediums that have had to confront this fact. Movies, television, even comics and novels have had their depictions of gender, race, and sexuality scrutinized. Video games are the latecomer, and as the medium has evolved and become bigger industry, it starts to get held to a higher standard of entertainment. This means, basic obvious objectification is no longer free from criticism.
Representation also is a way to challenge some of the more toxic elements of video game culture. If you haven't been paying attention, the past year has seen several news outlets pointing out how video game communities are being used to radicalize young men. This is not a problem that just sprung up over night. It is the product of years of sexist advertising, of prioritizing and empowering the white male experience at the cold of almost all other perspectives.
Games are an interesting medium, more than movies or comics or television, they invite players to inhabit the skins of people different than them. It can promote empathy and sympathy for characters whose lives and experiences are vastly different than your own. Representation doesn't just allow women and people of color or LGBTQ players to see themselves validated in the broader culture, it allows people who might otherwise not think about these groups to connect with them.
Objectification can damage good representation though. If a woman is presented more as meat to lusted over, then the character is rarely taken seriously, by either the story itself or the player. That is not the same as saying sex positive characters can't exist, but the subject is complicated. Factors like the male gaze of the camera, how well the character's personality is developed have to be taken into account. The worst possible outcome of constant objectification is when it is considered not just normal, but the standard for female representation. You can see this problem in how people are reacting to MK11's designs and how it is an attack on "boner culture". Anything less than a total sexpot is treated as prudish and is likened to forcing the characters to wear burkas. To summarize, rampant objectification has the side effect of warping the expectations and standards that designs for women have.
Finally we come to the elephant in the room, Gamergate. The poster you are defending praised a gamergater as an objective unbiased source of discussion. Not only is that wrong, it is essentially, supporting a hate group. Gamergate has lead numerous harassment campaigns against women who worked in the industry and games journalism. They have lead successful hate campaigns to get women fired from their jobs, and to make them fear for their lives. Their less radical supporters will frequently speak about how representation should happen "organically" in the industry, and that creators should not have to change their original vision to include any other perspectives in their worlds.
This creates an impossible situation where women are driven out of all areas of the industry due to harassment campaigns. They are shown if they speak up about gender, or sexism, or even just their desire to increase representation, then they will become a potential target. You see the problem? Gamergate demands that only women can create the kinds of representation people on this board ask for, but also does everything it can to drive women out of the industry. It's a hate group that has spent the last several years trying to deplatform women, and propping up its supporters here is the definition of arguing in bad faith.
I apologize for the wall of text, and I don't claim to speak for everyone here. I am trying to voice some of my perspective, as limited and flawed as it might be. There are many wonderful posters on this thread who could give better responses. I hope some of this has been helpful.
