Game 7 of this year's Final was the most-watched NHL game in the US in over 45 years. Overall, the average audience for this year's Final was the third largest since the Finals returned to network tv in the mid-90s. The only 2 Finals that had a larger average audience were 2013 (Chicago-Boston) and 2015 (Chicago-Tampa).
https://en.wikipedia.org/wiki/Stanle...vision_ratings
Overall, the NHL's national ratings in the US are much smaller than the other major leagues, but it's a generally consistent audience.
One big change that has happened in recent years is that overall tv ratings have declined sharply, but live sports have generally remained steady (or at least declined less than most primetime tv). Of the 5 games of the Final that aired on the main NBC network, all of them averaged more than 5 million total viewers. Of the 20 scripted series that aired on NBC last season, only 6 averaged more than 5 million viewers per episode. The 8.7 million people who tuned in to Game 7 of the Final was higher than the average viewership of any of NBC's scripted shows last season.
The NHL's new tv deal won't come close to the multibillion dollar deals that the NBA, MLB, and NFL have, but it should still see a significant rise over the current $200 million per year deal.
The current NBA contract pays the league about $2.7 billion per year. If the NHL can get a deal that's worth a quarter to a third of that, it would be a huge jump.
If the new deal were to increase by $320 million per year to $520 million, it would effectively raise the players' share (and the cap) by $5 million per team. If the new deal were to increase by $640 million per year to $840 million (still less than a third of what the NBA takes in), it would increase the players' share by $10 million per team.