I say this as a cis dude. Using another person's proper pronouns costs us _nothing_. It's just common courtesy.
Refusing to do so just makes you an asshole. The math isn't complicated on this one.
@Are0h It's simple. Like if a dude named James doesn't want you to call him Jimmy.
And if you slip and call him Jim and he corrects you, you say sorry and thanks you'll try harder.
@faehnrich @Are0h Exactly this. I make mistakes all the time. It's embarrassing when it happens, and I really do make a conscious effort to comply with the requests of others.
When (not if) a mistake is made, how you handle that situation is what determines the kind of person you really are. Either you gracefully accept the correction, integrate the lesson, and adjust accordingly; OR, you react with spiteful derision. The former is generally a good person to be with; the other insufferable.
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@faehnrich @Are0h Regrettably, I grew up in a conservative household that was racist and sexist. So, for me, I have 16+ years of habit and upbringing to consciously kick.
I do not mind one bit. Accepting and working with my fallibilities makes me a better person. Over the years, I've gotten a lot better at using correct pronouns automatically. I rarely have to think about it anymore.