The problem I have with these kind of advocates, though they may even be right, is the "may even be right" aspect of it. With slight alterations I feel like I've read the same stuff from proponents of Ten Hag and Amorim. Known but not top tier and a gamble. It might pay off but we've had only experience of these types failing and setting us back years.
I'd much prefer a top tier manager right now -- for a few years -- to get us back on track and then when the squad/team are back to cohesive winning ways, indeed, make such a gamble. But to give this team/squad now to a manager like that, and it's not like their Klopp at Dortmund where every blind man could see he had something special, -- to give them this job is madness imo.
We want an Ancellotti/Enqrique/Emery styled manager. Proven (especially two of them, the first two, though I have lots of respect for Emery, too, and he is, in some ways, my first choice), will attract players to a project because they all (first two especially) basically guarantee some kind of success. If you were Anderson and knew we'd be coached by Ancelotti/Enrique, you'd think "that's very attractive - to play under the best in the game outside of pep.. basically". Be part of the new build which drags us back to the top. Any involved in that, when it inevitably does happen, will retain legend status in a way that will transcend their careers as mere footballers. Only United, really, offers that kind of reward given the size of the supporter base and when we're winning we really are the most famous name in sport.