PER can be a pretty shitty stat, sometimes, though. Kawhi was the 2nd best player in the league for sure this year. His PER is lower than:
Curry's
Lebron's
Durant's
Westbrook's
Paul's
Marjanovic's (lmfao)
yet when we add win shares, we see that Kawhi was 2nd in the league in ws/48, and he was 4th in BPM as well. There's also the cases where somehow Kareem's highest PER was 29.9 yet in the same season he posted (by far) the best ws/48 in NBA history (.340).
Alot of pts/assists/rebounds has to do with pace, tbh. Russell Westbrook pace-wise would have averaged a monstrous triple double in 1961-1962, for example.