There is so much randomness in first or second assists that the whole argument is silly.
Just two examples from the Florida series:
Nylander carries the puck into the zone, draws two players to him, and feeds a wide open Marner for a quick pass to a wide open Matthews for an easy goal. Goal by Matty, first assist by Mitch, second assist by Nylander.
Brodie (?) takes the puck off a Panther and passes it up ice, it tips off Tavares' stick and Nylander picks it up, skates into the zone, and scores. First assist by Tavares who just happened to touch the puck, second assist to Brodie.
In both cases it could easily be argued that the second assist was the more important one. Sometimes the third assist is the critical one.