I think one of the big problems is that the men and woman play different games.
In general as spectators we want to watch sports that are high skill with a big physical edge.
I'm not a 100% sure if I am right or not, but it seems the rules for womans hockey are very restricted. The lack of big body checks and yes fighting really take a lot of excitement out of the game.
Got to say I would be way more interested in a (WNHL) if the rules were more open, allowing big hits and fights.
Also as others have said, 1 league In North America would also increase the skill level (of course travel cost would also increase).
Found this article after a quick search
https://thehockeywriters.com/hitting...ockey-why-not/
Hope to see a future league with stability for all these hard working athletes.