The movie/TV companies sell their show to the SVOD platform that offers the most in the territory. Or it's developed by the service themselves. So if you have to subscribe to a handful of services to watch everything your friends recommend.
Most of us can afford one music service. If you're forced into 5 streaming services a lot of people will just pirate. And even for those that do pay - the "we'll show this in the UK a week later than the US" means unless you pirate it, it's spoiled on social media within a few days.
And for video it wouldn't have to be $15. People easily pay $50-80 for cable channel packages. A comprehensive streaming service could cost similar. The willingness to pay is there. I'm just really sick of this shit paying for tons of different services.
When Netflix was the only game in town I subscribed to it. And prime later. But now I've dropped all my subs and gone back to the jolly roger. As have many people I know.
We have a saying in Holland: he who looks too deep in the can gets the lid on his nose. It's a bit akin to the American saying of having your cake and eat it. But the thing is there's lucky so many profits you can extract especially if you're competing with free but more hassle.