Ecosystems are either too fragmented or too monopolistic.
In this case, it's actually both at the same time! No, for real, that's why it sucks so bad, both of those things are simultaneously problems with the streaming service market.
Another poster in this thread has already posted my personal preferred solution, which is to do the same thing we did to movie studios and movie theater ownership for many decades, ending only a few years ago: ban combined ownership of both production and distribution.