My hot take on this is always that it kind of is what it is.
I get why hockey is niche, to be completely honest.
I enjoy it, but I completely understand the reasons why most viewers would look at it and go "eh, this is a bit stupid."
People tune in to watch the same players and teams that they hate over and over again. They like to watch the best players and teams go to work and win with skill. Hockey is very chaotic. It's fast, it's bouncy, and anybody can beat anybody.
People say they want that but then they turn around and watch the Yankees, the Lakers, and the Chiefs. People 'like' underdogs and randomness...but they don't f***ing watch it.
It's like, I listen to death metal. I enjoy it. I 100% understand why people wouldn't want to hear it. It's fine. The thing you like doesn't have to be overwhelmingly popular. It's bad for your ticket prices. That's the way I look at it.
I also think one factor is that for a newcomer to the sport, watching a game on television when you're new to the sport, it's kind of hard to follow the action. As for myself, while it's often the case that I can't actually see the puck, I know the ins and outs of the game pretty well so I can usually tell where it is and anticipate where it's going (though sometimes my anticipation for where it's going to end up turns out to be incorrect). When I first started watching, it was on TV and a little hard to follow because I was new, but I actually went to a game pretty soon after starting to watch the Coyotes, and it was a very different (and much better) experience than watching on TV. That's probably what got me really hooked on the sport.
I don't think it's much of a stretch of the imagination that there are people who try watching hockey on TV at first, find it difficult to follow the action, never make it to a game in person, then write it off because they can't get into it.