Think in Tomori’s case having 4 CBs was an overkill especially with 3 in their early to mid 20s. Sooner or later someone was going to be left out in the cold. He should have been loaned out to get another full season, and Guehi drafted in his place. Your 4th defender should either be someone at the tail end of their career; a Lovren/Otamendi or a young player from your development squad; an Eric Garcia.For sure, he represents less talent. For starters who knows his best position? Take a look around at who would be clamoring for his services if he was on the chopping block.
FWIW I think the club need to figure out which position they want to see him play before anything. This is one thing that Tomori was also dealing with. He's played so much CB and RB, he was neither
Same applies to the wingers; having 4 wingers is an overkill. 15yrs ago you could get away with rotating your team constantly to keep them fresh, nowadays you are better off keeping a leaner squad to keep every one motivated. Especially when you consider some players might be deemed multifunctional; like your Mount. You could argue CHO wasted a year also when he could have been loaned out and playing regularly. Next season with Pulisic, Ziyech, Werner capable of filling in, potentially Havertz if we get him and Mount if he continues viewing him as a pseudo winger, there is no reason to keep CHO stuck on the bench and feeding off scraps. Liverpool have Minamino, Shaqiri & Chamberlain filling in for their 2 wingers, James is the spare winger at Utd, Foden is filling in as the 4th winger at City.