So he played the best hockey of his life with us (see especially 2022/23 season), what kind of fall are we talking about? See his overall stats. His own play was spoiled by his PP. He just didn't have as many goals because of it. 5v5 was all fine and would have been more if he passed more in transition, which he can do, he showed it more than once.
Or better:
2022/23
Reinhart
82 games 5v5 9, PP 16, SH 6, all = 31
M. Tkachuk
79 games 5v5 22, PP 14, all = 40
P.S. I was wrong MT had 14 in 2023/24
Rantanen
82 games 5v5 32, PP 13, all = 55
Matthews
74 games 5v5 26, PP 13, all = 40
Laine
55 games 5v5 13, PP 8, all = 22
if 82: 5v5 19 versus 9 Reinhart and 32 Rantanen
if 79: 5v5 19 versus 22 Tkachuk
if 74: 5v5 17 versus 26 Matthews
(do not forget he was 3x injured and he had to return his shape)
Partners (I hope you see this difference):