Maybe the OP title is too definitive, yes. There are also one or two instances where someone has said in this thread, "as a queer person, this was my take on something" only to have someone else go "well actually."
But by and large, I think people in this thread would actually be pretty receptive to someone coming in and saying, well, I'm queer, and I disagree with the original argument. The person talking about how they saw much of themselves in Kanji, despite what later happens to the character, is valuable insight. There were a bunch of articles a few months/years after the release of Persona 4 that really grappled with the question of whether Kanji and Naoto's characterizations were problematic or offensive, and even back then the jury was kind of out on the matter. It's always more interesting to hear people who grew up questioning or queer try to make sense of Kanji's storyline and say, "yes, that feels true to me," or "no, I think this put a foot wrong."
I'm not queer, but I can kind of see both sides on both characters--the fact that Atlus kind of pulls back on overtly marking those characters as queer can be a disappointing thing for people who want to see obvious representation in games, but at the same time it also seems like there was a genuine attempt to at least address some of those issues, and that people found parts of themselves reflected in those characters (something that I feel is lacking to an extent in Persona 5, where so much of the stuff people find offensive is partially because it feels so casually tossed off). Rarely are representations of different identities totally perfect; indeed, you can argue that they have to be imperfect to be considered real.
Like, to change the context and make it racial (because that's something I do have some experience with), Asians in western culture are so often depicted as the "model minority" that to have an Asian character that is actually evil or selfish can itself be transgressive/progressive. There's so much pressure to depict minorities as innately good that they stop being actual people and turn into two-dimensional characters, there solely to support a specific message about racial integration rather than being allowed to breathe and live as other characters are. Having characters who are not completely 100% devoted to a queer identity, or question it and are in the process of figuring out who they are, is never going to be a perfect archetype of a queer person. But maybe, potentially, it feels more true to actual human beings, as opposed to a utopian image of what a gay or trans person should be.
But at the same time I totally get the impulse to say, "if you don't have lived experience, there is a level on which you cannot have this conversation." There are always going to be some things I will never understand about the queer experience, never feel with every fiber of my being, and so on some level anything I say will always be a little academic and a little distant. I don't think the answer is to cut myself out of those discussions, but I think some deference to people who do have real experience is warranted. In other words, I'm happy to say my piece and discuss with people, but I'm not really going to be upset if someone comes in and says "I'm queer and I think what you're saying is wrong, and here's my experience with those things to explain why." It's not really my right.
I guess what I'm saying is, I like this discussion and want to see more people of diverse experiences taking part in it, but also I don't think the OP meant to start the discussion in bad faith. It's not for me to moderate or referee the discussion, of course, so I'll just end my piece there.