I think someone saying it to say "hey, you..." to me, or "omg" or "woah" is different than when they mean "you look masculine." Those are some of the different ways I hear the word dude. Usage matters.
I think I don't understand genderfluidity for others in this way. I know some people that do not go by she/he pronouns exist, but I only understand having she/he/they all at once. If there are resources or experiences you guys can share about being genderfluid and not going by either she or he that'd probably help me understand a better picture of how other people's genderfluidities can work.

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