if you call everyone dude and a transfem person gets mad about it, don't get defensive. just say like "sorry, i won't do it again" and don't argue "actually it's gender neutral" or "i call everyone dude". even if you do, i guarantee she's heard that argument from someone who very much does not call people they see as women dude. i certainly have
same goes double for the word guy.
Yeah, that's the thing. I have a friend who's enby and transitioned over the time I knew them. Ran into them earlier this year, and casually dropped a "dude" out of habit/forgetting, and then was like, "is that OK with you?" They're fine with it, but if they ever expressed otherwise I'd do my best not to call them that.
It's not rocket science. Just because I can call a woman "dude" doesn't magically change the meaning of the word.