See, I think it will. If you add two teams, you add roughly 40-50 players to the league.
The majority of that, say 35-40, will merely be your higher-end AHL talent that couldn't stick with an NHL roster. And the others will be the over-the-hill vets that no ones wants but will get signed to plug a hole. You might get a few randos from European leagues but I imagine no more or less than usual.
Just a basic normalized distribution tells you that if you increase the population size, you will be diluting of the mean because we are not adding top talent on the other end. If they were there to add, they would already be in the league. Not like there are 20 1Cs over in Europe or the KHL that can't get an NHL deal. Instead, you're adding several AHL/AAAA players. So yeah, overall weaker. I do not agree with your premise.