I don’t think this is a coaching problem. The team has just been lazy and not doing the little things they were doing last year. Maybe they are focusing on stopping the three ball too much and need to go back too dominating the paint defensively.
Lopez is a bad defender the further away from the basket he gets. He just can’t move like he used to. Middleton also looks like he is no longer above average defensively.
Beasley is probably the biggest problem defensively along with Portis. Portis just doesn’t look the same defensively or offensively as he did last year.
I think this team is just getting old and are not elite defensively anymore other the Giannis and then Lopez as long as he doesn’t have to move away from the basket. I just don’t believe this team will get much better defensively. There just isn’t anywhere to improve or get improvement from a trade.