I get that and as I said, I don't agree with how they have applied their policy in some cases, but it illustrates that they have always had a say over what content you get to play, and that most have no issue with that in principle on any console. All three companies 'could' allow the publication of AO rated games, but blanket ban them instead, making the choice for you.
The problem for me is not the removal of specific content, but rather not clearly defining what is and is not allowed. Aside from the harm to developers, you cannot well argue against, or reasonably agree with something that is so undefined. Sony should set out what has changed, what is allowed and what is not.
That is deliberately done though. By being vague about the policy, it makes it far easier to deflect criticism.
By not drawing a line in the sand, people won't know which games are censored vs which ones aren't. Therefore, people who might otherwise choose to buy a game on a competing platform will unknowingly buy the censored PS4 version instead. If the recent DMC censoring hadn't been brought to light so soon, it would've gone exactly as Sony wanted.
By being vague, it also allows for Sony to play favorites if you will. They can force devs to censor anything even remotely sexual, while allowing first party devs to release whatever they want, such as what we'll likely see in TLOU2.
Sony claiming some kind of moral high ground here is absurd.