I've seen a few posts recently calling people out for using "they" when referring to someone with gendered or neo pronouns.

As a long time dumb guy I was under the impression that gender neutral pronouns were basically always acceptable and I'm now concerned that I have been unintentionally making people uncomfortable.

My current understanding based on context is that once someone has made their pronouns known, unless specifically included, 'they' is no longer acceptable. Thank you in advance for taking the time to help me out