So you'd be cool with some guy doing this to your daughter/sister/mother if he kicked ball? Strange.
I look at it in 2 lenses. Legally and from Prem/Club player conduct policy.
IMO, There has be a violation from a legal standpoint and/or a league/club player conduct policy.
The legal case has been dropped and unless there is clear policy in the Prem/United that states behaviour X,Y or Z could be grounds for termination of a contract then he should be allowed to play.
I think the NFL, NBA etc all have rules about players off-field behaviour while still in the league. The Prem should adopt it so there’s clarity if not players are in the court of public opinion.
All this “what if he did this to your mom/sister etc” is a bit of whataboutism. That’s not the scenario at hand.
If United don’t want him due to the fallout from public opinion, then just pay out his contract and move on from him.