Not sure why you’re simultaneously arguing that international form/performances are irrelevant in the same post that you discuss his international form/performances.
In my opinion, they’re clearly relevant. If he was consistently looking like a £90m footballer every time he plays for France then that would give a lot of weight to the argument that both Mourinho and Ole have been playing him in the wrong position, wrong tactics, or with the wrong team-mates (or all three) Which are points that have been made a zillion times in this thread.
When he flatters to deceive for club and country (and I’m 100% in agreement with you that he wasn’t actually all that impressive in the WC) then it looks more and more that he just isn’t as good a player as we hoped he would be.
Even his time at Juve is nowhere near as impressive as you’d think. His statistics improved, on almost every single metric, after moving to United.