Why do people purposely call trans people by their old pronouns?

Look I get that some people might not agree with a certain lifestyle but at the end of the day we are all human and those of us that aren’t murderers and rapists deserve respect so I don’t think it’s too much to ask for people to be called what they want to be called, like my aunt always told me “you don’t have to agree with something to respect it”
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For all of you guys going anonymous and writing down transphobic things, if you believe this things why are you so scared for people to see the real you, you clearly have balls to come on here and say rude things have the balls to go public
Why do people purposely call trans people by their old pronouns?
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