I agree with you, mostly.
And I’ve seen the opinion expressed a lot. Which means I can’t really call it unpopular, though it also isn’t a majority opinion either.
Where I would disagree is that his performance wasn’t his best overall, despite it being his best movie. A good bit of the work involved came from direction, editing, and the rest of the cast as well. He didn’t, however, do great delivering his lines.
Where I agree is that he didn’t have a lot of lines. Most of what made the character shine was physical and facial. That’s where he was great. He still is superb at that; he plays for the back rows, and it works.
For sure though, it’s still his best movie overall
I’m with you on Devil’s Haircut. Just a great example of what he does.