Just want to point out, if these are the current world class coaches:
Erik ten Hag is 51 years old and have coached Ajax for four years, before that Bayern II and a couple of minor dutch teams. He had one good run in the CL and has won the dutch league.
Flick had worked for 15 years as an assistant, suddenly was world class after bringing Bayern a CL.
Nagelsmann is pretty unproven right now I'd say. A lot of hype obviously, but what proof is there of him handling a world class squad to regular trophies? Did he win ANY title yet?
Klopp and Tuchel I don't know, I guess these two german coaches have worked themselves up and proven to be world class through good results at Mainz and then Dortmund...
Pep is very much proven right now, but, as we know, wasn't proven when he got the job.
Yes, as with Rijkaard or with Pep.
The job of those deciding on the next coach is to have a sense of who would fit at Barcelona and make the right decisions here, in the unique situation of the club. It's not at all about listing trophies at other places, or who is "world class" or not. If you do that you are at least one step behind.
Koeman is more and more proven to not be the right man.