For all the talk of certain points not really mattering, I'd say FLA showed in Game Five why goals to put a team ahead by three, four or even five goals can be important.
The score was 2-0 when McDavid scored his first goal. He makes it 3-0. FLA scored to make it 3-1. He then assists on Perry's goal that makes the score 4-1. At the time, EDM appears to be in cruise control. But that goal ends up being the game winner and FLA applied a lot of pressure late in the game.
It's best to avoid situations like that altogether. McDavid's goal in Game Four gave his team a three goal lead as well, and I'd say even Nurse's goal (that he assisted on) wasn't meaningless. That one basically broke FLA's back. The other two points were overkill, but you shouldn't take your foot off the pedal.
In Game Three, I think both of his assists were important as the Oilers made an attempted comeback of their own. He also set up McLeod for a good scoring chance from the slot after the 4-3 goal. If McLeod had scored there, it would have been a tied game.