I called Langone hospital (646-929-7870) asked to be transferred to the maternity ward, and asked the witch who answered:
“Do visitors need to be vaccinated?”
Response: “So, umm, you either need to have proof of vaccination, or a negative test in the last 24-48 hours.”
I forgot to ask if unvaccinated parents will have their newborns kept from them if they’re not vaccinated. I’ll call back tomorrow and ask.