

First of all, this is not a professional setting, he’s not an employee there, and that forum is open for everyone.
Secondly, and way more important, people do that daily and no one cares especially when introducing oneself it’s common to mention stuff like your wife/husband and your preferred pronouns, hell, my corporate slack profile has my pronouns and those of everyone else. I’ve worked with trans people who introduced themselves as trans on the first day, and no one cared. So no, it’s perfectly okay for people to talk about themselves during an introduction even in professional settings.
Last but not least, people being uncomfortable is not a good reason to ban something, members of the KKK might be uncomfortable about working next to a black person, so what? Should the black person hide that he’s black to not make the others uncomfortable? That’s bullshit. If a person is uncomfortable by another one saying they’re queer, then that first person needs to deal with it, being queer is part of who the other person is and he shouldn’t have to hide who he is because someone might be uncomfortable about it. You mentioned religion, which I don’t think falls into the same category because religion is a set of beliefs that many people change through their lives, but still, people wear crosses daily in professional settings and no one cares.
How is it political to talk about yourself in vague terms when introducing yourself to a group!? Would it be political if he said his hair is brown? How about if he mentions the color of his skin, is that political?
You make the statement political when you try to ban certain people from talking about who they are, if only white people talk about the color of their skin it’s not political to say you’re black, it’s political to try to block people from saying it. Saying you’re queer is on the same level of mentioning you have a wife/husband, in fact it’s even more vague, it’s in the same level of saying “since I was a boy/girl”, because queer does not necessarily mean non-heterosexual it can also mean non-cisgender so it’s an umbrella term to mean member of the LGBTQ+ community, if being queer is political then being heterosexual or cisgender also has to be, and I doubt people would be okay with having to step on eggshells not to mention anything that could make someone deduce their sexuality or gender. Hell, the same people who claim Queer is political are the ones who have the most problem with gender neutral language.