I mean there's a simple answer here - you can be fit enough to do light training but not fit enough to compete in an international fixture.
Nothing to see here.
It's just his style. I picked up on that too, but I don't think it's something you actually need to train out of him. Let's see what he's like when he's in his best position and back in form.
In the same sense I'd rather replace Willock with someone like Frenkie de Jong.
Wilson's got at least another 2 years with us, and with the right team around him he'll score loads.