Being rude and condescending back didn't improve the situation.

You were correct, factually, and they were wrong. People don't like being told that they're wrong and being rude is one of the more common reactions. If you're going to try to engage with people on topics where there is a lot of ignorance and misinformation you'll encounter that a lot.

If you're just going to hit back then you're going to be spending a lot of time pissed off and wasting your time trash talking people who don't care what you have to say. To me, that tactic generates a lot of headache and no gain. Once it gets toxic I'd rather disengage or write as if I'm addressing the other members of the community who are reading along. Lemmy is still small enough where you can recognize people and develop a reputation so taking the high ground vs toxic people can pay dividends in terms of having other people listen to your opinions.