It should not be like that. And it has little to do with the current central defenders in the squad.
It can't be stressed enough how important stability, system and confidence are for central defenders.
There are so many examples with good defenders underperforming in a weak team and OK players looking great in good teams.
Leicester have Jonny Evans. He made Harry Maguire a £80M player. The next season Söyüncü looked fantastic next to Evans. Before they signed a teenager from France that looked world class from day 1 in Premier League. Same with James Justin. But as soon as Evans is missing from the starting eleven, the Leicester defence is [Poor language removed].
Rudiger became a scapegoat when Lampard was fired from Chelsea. He had been poor formonths. Lots of Chelsea fans hoped to never see him play for Chelsea again. Looked like a new player from the day Tuchel came in and was probably the league's best central defender in 2021.
Eric Dier was shocking after he told Mourinho that he no longer wanted to play midfield. Same under Nuno. Since Conte was hired, Dier has probably been the best central defender with UK passport.
Varane was among the best central defenders in the world for years. World champion. 4 times Champions League winner. The United defence with Varane was the worst defence they have had for decades.
Mason Holgate was trusted by Big Dunc after Silva was fired. He did very well. He became Ancelotti's first choice. He was voted player's player for the season. Covid-19 stopped his England call-up. He injured himself in preseason two years ago. Why Everton signed Godfrey. Back from injury Holgate struggled. Moved around. Often had to play out of position. Since Lampard came in Holgate has been a lot better than what he gets credit for.
Godfrey was good his first season. Underwhelming last season (as most Everton players were). Will improve if he can stay fit.
Mina is for Everton what Evans is for Leicester. Not a brilliant defender, but players around him look so much better and more assured when he plays. Two seasons in a row now where Everton with and without Mina have been two different teams.
Keane is the one I struggle with. But if the defensive problems Everton has as a team are fixed, I am sure he can do a job.
Holgate's 19/20 season and Godfrey's 20/21 season were better than any Everton player last season. They would have walked into the defence and improved better teams than Everton. A poor season for a non-functional team doesn't mean they are bad players.