Is there a source to say this censorship was called for by Sony?
I'm not doubting the possibility but I find it strange considering how much mature content is on the system. The Witcher 3 wasn't censored. After the rumors of censorship for Nier: Automata, perhaps because of internet uproar, that game and the protagonists buttcheeks weren't censored either. The Last of Us 2 has shown girl on girl action in its previews.
Is this a move by the publisher, because they might have thought a mainstream audience in NA couldn't handle the extra booby physics, where as a secondary demographic like that on the Switch my find it as a good selling point since they get something the original release didn't?
I have no stake in this since I find the content silly, but I'd like to know if Sony is really at fault here?
There have been multiple reports about censorship on Sony systems and the number of titles that gets censored on PS4 while saw a release with all the lewd content on Switch have been increasing the last few months.
This is a rather recent occurring, and that would be why those games you mentioned haven't been affected - and also that thing happening affects mostly those mid-tier japanese devs. I don't know if Sony would be going after the western devs and the AAA, they have much to lose if they messed up their relationship with them. Also about The Last of Us 2, I am not really aware of what happens in the game besides the lesbian couple, but I don't think it have sexual content worth of censorship.