The biggest thing I want to highlight with his time at Al-Sadd is how difficult it is to get players of that quality playing the sort of football they were playing, considering just how different tactically they were before he arrived.
In terms of lack of experience in Europe, what I would say is that if he can get the results against the likes of Real and Atleti, then we can ride that sort of momentum and form into Europe that can help overcome this being new territory for him. And in all fairness, it isnt like he hasnt managed and won some high pressure games for Al-Sadd in knockout tournaments. Sure the quality is clearly non-comparable but the way you go about doing well in those tournaments, the preparation and training, that is all the same. And he has trophies (read that as plural) in these knockout tournaments that are similar in structure and format to the CL.
He knows La Liga well and considering that quite a few teams rn here are employing the same sort of brexit-ball they were running in Qatar, I think he has the tools to at least stabilize our La Liga form which for right now, is most important. We need to focus first on dominating Spain first before we worry about Europe so I think the waffle about not being in Europe is kinda overrated when you really think on it and really look at what he has been doing in Qatar, biases on the quality aside.