And even if I was swimming in money, it's often easier to just download the shows I want and watch them on Plex/Jellyfin than trying to navigate the (often ad-riddled) interfaces of the various platforms and finding where the content I want is.
One example is Rick and Morty, it's made by Adult Swim, but they don't have a streaming service in Canada. It seems to be on Primevideo but under a different system than their regular content. The other way to watch it is to buy it from my cable provider (I don't have cable). So to watch a 20-minutes animated show I'd have to take a +40$ subscription.
Western shows get more formulaic by the day and anecdotally most of my friends that watch anime watch 98% anime and 2% occasional popular show on netflix.
Anime fans will be more likely to drop non-anime streaming services in favor of additional anime streaming services. e.g. trade Hulu for HiDive