He will always be a bad defender player, because with his size and lack of wingspan and strenght it’s impossible not to be especially in the current era.
But in the last 2 seasons I’ll say he has gone from absolute worst defender in the world to at least showing effort when I saw him, not sure if it’s consistent, but still
They have A LOT of defensive talent, Brooks, Tate and Eason are all All defense level, FVV, Jabari and Holiday are all between good and very good, Sengun has improved a lot too