I'm not really sure what the NFL is supposed to do here. How long can you realistically suspend someone based purely on accusations and nothing actually proven? Obviously, Watson DESERVES more than 6 games based on what he likely did. He probably doesn't deserve to ever play again. But that's not really realistic for the NFL to hand down that kind of a ban on a whim.
Ideally, the teams wouldn't acquire these types of players, and that's how these players would get punished, but talent always outweighs baggage if you're talented enough.
Once the NFL tried to start policing off-field stuff with suspensions, they are going to look like hypocrites with suspension lengths. Alvin Kamara will be another example. It seems like he'll play this year without a punishment because that case is getting delayed. But you know if the video of his actions was ever leaked publicly, he would get an immediate suspension. There's no good way for the NFL to do this.
I blame the Browns far more than the NFL. The way that contract is structured is disgusting, and they could have made the decision not to acquire him.