Fox has Luke Walton for a coach and a team that just now handed him the keys this season or last. Comparing him to Trae or any of those other guys doesn't make much sense
Why? And keep in mind, Fox is a big part of why Walton is coming back next year, which should tell you all you need to know about whether Fox himself believes that the problem is Walton. You can't back a coach and then not be held accountable just because you're playing for that coach.
Also, Fox has had the keys as long as Doncic/Trae have. Season #1 was the whole George Hill/ZBo thing; by season #2 we were run and gun under Joerger, which was Luka/Trae's rookie season.