The problem lies with users who default to they/them even after being informed of the correct pronouns, especially users who continue to do so in the same comment thread. Making mistakes is going to happen, but quickly apologizing (even if you're arguing) and editing your message to resolve the mistake is the bare minimum. Even as a mod I really only recognize a few users and remember their pronouns (honestly, mostly because they overuse the reporting system), but when I engage with or talk about users I check profiles to see if any pronouns are posted in the bio. This is a trans-inclusive queer instance, respecting gender identity (YES EVEN CIS-HETERO PEOPLE) is incredibly important.