Maybe I'm an optimist but I think there are quite a few managers who can right this ship.
We didn't lose because of a lack of talent. We lost due to injuries to key player(s) (mostly Bremer), a regularly depleted backline (and no Huijsen or sufficient rotation options), key players not playing to their level (Vlahovic stands out the most here), and key purchases not playing to their previous ability (Luiz, Koopmeiners specifically).
There could be any number of reasons for these but the LEAST likely reason in my opinion is that these players all suddenly forgot how to play the game to a proper level. Motta's system and rigid adherance to that system, Motta's inability to control the locker room, lack of leadership in the locker room when we started to spiral, lack of leadership on the field specifically in CL but throughout the season we could not maintain a lead and fell apart regularly from winning positions, lack of players playing to their abilities, and injuries that decimated our first team and backline specifically to the point we had two fullbacks playing CB for the last 1-2 months of the season.
That's a lot to cope with for ANY team and adding a new manager on top who doesn't have the control of the locker room only compounds these matters. Tudor did show that a manager the players respect can help but even with him we had a meltdown.
We need structure and stability from the manager who is willing to adjust his system to the players and injuries we have and who commands respect and instill confidence and leadership to the players.
It's possible but it won't be easy and those types of managers are rare.