Well most Trans people change there name like if thay originally had a more feminine name and thay transitioned to male then thay would change there name to something more masculine or something that suits them. the name thay had before thay changed it is called a dead name
Fr thay act like it effects them in some way if someone else is trans and it's just really annoying and upsetting when even your friends don't respect it by calling you by your dead name and stuff