I was one of the few posters defending Fred when he first joined. But things have turned too far the other way on the Forum these days, imo.
Fred seems to be getting overrated simply for not being shit. It's great that that he's turned the corner, but his game wouldn't get him considered as much more than a continuity player at any other decent side. And even since his upturn in form, he still gets easily bullied when the other team decide to put him under any pressure.
McTominay may not be a world beater, but he has fewer exploitable weaknesses and offers more of a threat in the opposition half. You might lose a bit in terms of long range passing, but you gain more overall. I think he's clearly the superior player.
Fred is overrated mostly because Mctominay got injured in December, up to that point, it was quite clear Mctominay was having the better season. Matic has also been better than Fred since coming back in my opinion. Fans of Herrera are the people who like Fred because their games are similar. They press heavily without much success and are adequate at stringing passes together against lower opposition teams. What people don't see is that both have a poor sense of positioning both in and out of possession and are primary reasons for why we struggle to bring the ball out of defence at times. In addition to this, Fred in particular has a poor first touch and in big games where pressure is highest, he frequently loses possession for us, meanwhile Mctominay, even though seeming less busy, consistently wins aerial duels, interceptions and tackles in those games. In addition, in possession, Fred is not great at driving with the ball and neither he nor Mctominay as of yet are good at creating or scoring chances, even though Mctominay is showing vast improvements in the latter. Mctominay barely makes mistakes in the game, gives us a certain steel in midfield, can hold the ball and has good balance and agility which allows him to drive forward. His passing isn't great but it is much better than it was prior and is clearly being worked on given his small level of experience. He is not great at dictating the tempo of games and may never be, but has shown the propensity to make good passing decisions in tough situations, something that Fred constantly fails at. Fred is a solid bench option in my opinion, and in truth the 50m price tag, the previous exposure he had at Shakhtar, despite his failings last season and his busy game make our fans feel that he is much better than he actually is. For me he could become a really solid utility player here given how many midfield roles he can cover.
Aside from performance, another factor is that both Mctominay and Matic' weaknesses can be masked by playing alongside both Pogba and Bruno, which will allow them focus on the areas they are best at. Fred's non stop pressing would expose the midfield. He may be useful for games against lower quality opposition in which we need to break down a deep block, but aside from that, playing him alongside Pogba makes no sense.