I think some coaches are more suited to underdogs while some are more suited to being the dominant team. Xavi is certainly in the latter class. I Don think this is something often considered when assessing potential coaches
A coach who is suited to being an underdog does not have the ability to be anything else. It’s basically another way of saying they are not a top level coach. A coach who doesn’t know how to coach a dominant team is not an elite level coach. Very few “non dominant” teams play at the elite level anymore - Simone‘s Athletico being the last. This is why you see lots of coaches with “cup” success- because on his day, a non-dominant coach can eek out a result against anyone (see Ole v PSG!).
All other elite level coaches are comfortable having the majority of the ball and know how to use it without having to be up in the 70% possession stats. Tuchel, Rodgers, Zidane, Naglesmann, Rose, Poch, Ten HAag, Allegri, Conte, Sarri...all elite managers...none dominate the ball like Klopp or Pep...but all have distinct styles when in possession that allow them to go toe to toe with any team.
When you don’t have a coach with that ability- you counter attack...Jose and Ole are very similar in that regard and would never even consider going toe to toe with top sides. Man Utd are too big to not have a coach who has a distinct identity in possession.