the constitution is a legal document and it’s been amended 27 times

It IS a legal document though. That isn’t something you should be able to alter because of anyone’s feelings.

What a silly argument. We have legal documents that change because of peoples feelings used all the time. What do you think Marriage licenses and Divorce decrees are? How does someone changing their their birth certificate hurt you…at all?! Can you name one single person that has change their gender on their birth certificate? No of course not. Neither can I, because it doesn’t affect either of us at all. The only person it hurts to restrict changing is the person itself. Why do you intentionally want to cause someone suffering when it doesn’t affect ANYONE ELSE NEGATIVELY?

It’s a record of birth that you use to verify your identity. Gender doesn’t need to be on there at all - “Oh, it says on this birth certificate that you’re a boy, so I guess we know for sure that you are indeed Steve Smith!” But if it’s on there, it should match the gender that the adult identifies/presents as. There’s no reason the DMV needs to know what your genitals were (or, really, what the doctor thought your genitals looked like) when you were born. Imagine any other private information about your physical body being a public record - “We’ll start processing your home loan now, Mr. Smith, sorry that you were born without nipples. That’s gotta be rough!” It’s stupid. And, of course, it’s also cruel. But you seem pretty unbothered by that part.

The main issue with these specific legal documents though is that often if you can’t change your birth cert you can’t change your passport or driver’s license and those two things are way more impactful.

Travelling as a trans person can be incredibly scary. If you look, sound and act like something not listed in the sex category of your documents there’s a solid chance that your documents will be treated as suspicious or if you happen to be in a place where people aren’t shy about being bigoted it gives an avenue that immediately flags you as trans can offer people the pretext to detain, harass and abuse you or to deny you services. Being strip or cavity searched by airport security to sate their personal curiosities is a real threat.

Being as invisible as possible offers safety to trans people from bigotry particularly during vulnerable moments of dealing with authorities. If you have physically transitioned then some times you can’t pass as your birth gender anymore which means your documents, adhereing to some sort of perfunctory definition of sex can make you actually less safe. It’s not about “feelings”.