This is top level football, there will always be criticism and Maguire isn't being protected by himself or Southgate. Ten Hag has done exactly the right thing, drop him for better performing players.
The only reason people are talking about Maguire is because he's being played and exposed time and time again, it's not a one off. The best thing for his career is to move to a different team with less demands and maybe take a short break from England. There's a player there in the right system, but absolutely not ETH'S system.
Southgate is in the wrong here, 100%.