Yeah I think the weight loss is a smart move.
Re his box and move tactics, it doesn't look natural to him in my eyes.
I agree that he can't be a front foot bulldozer with a weak defence and tendency to walk onto punches, but he seems to me to have overcompensated by trying to appropriate the opposite style.
All he had to do was tighten up his guard and be more selective in his punching. Cut out the bravado.
I don't think he has the boxing ability to be a slick, backfoot counterpuncher, but he could be a fantastic front foot fighter with small changes. I think this would have made for a more convincing win vs Ruiz.
It'll be interesting to see how he decides to fight v Usyk or Whyte. If I was Fury or Wilder, I'd fancy a go at Joshua straight away, before he gets his momentum back.