Help. Advice.

Bf is questioning singing the birth certificate bc i guess the state will force him to pay me child even though we are together. (not married) He said he doesn’t want to be forced to pay child support when we are together. I understand his point and i too think it’s kinda dumb that he would have to pay even though we are together but at the same time if it were me i’d do it no matter what bc that’s my child & he was going to financially support her anyway.. now the state would just “force” him to. I tried explaining to him if he wouldn’t sign it baby would get my last name & he would get absolutely no legal rights & to the state that wouldn’t be his child. he basically said “that’s my child i don’t care what anyone says” i don’t think he really understands. advice? please no rude comments, i’m already going through so much and am so stressed & depressed so im just looking for someone’s outlook.