It’s true that there are better holistic solutions. If it’s difficult to make a Roku player it may not be worth pursuing and I see your position and point. It seems like Roku apps are straightforward to build and maintain compared to mobile apps (I could be completely wrong there, they just seem like simple apps that don’t update often).
There are 80 million active Roku users as of 23Q4, and you’d be one of ten installed apps on the device for most people. That’s a decent surface area for engagement on a platform where every app has purchases.
https://www.statista.com/statistics/714052/roku-monthly-streamers/