As someone who rarely watch movies/series, I was paying ~100$/month worth of subscriptions until I cancelled most recently. Why? Content fragmentation is mentioned by everyone, but to me, the main problem was that I could never get a proper watching experience even after finding what I wanted:

1- English subtitles only available with CC: I want subtitles because as a non-native English speaker I cannot understand some of the accents. I hate it when the subtitle says: "glooming musinca playing"

2- Quality issues: I'm watching on a 4k OLED TV. Watching the matrix reloaded for the 10th time, and seeing the actors appear in two places because of some weird compression artifact pulled the plug for me.

3- Quality issues: I used to buy Crave's 4k subscription. It limits content to 720p on my Linux machine. Let's imagine a world in which I'm OK with it, IT DOES NOT GET PROPERLY FULL SCREEN ON ANY OF MY MONITORS/TV. I paid for a 65" TV, I want to see a video fill at least one of the dimensions.

4- UX issues: Sometimes I pause because I want to check something in this scene. Do not dim the scene, I'm not interested in all the details you are spitting to the screen.

5- UX issues: I'm not OK with you showing me ads before I start watching my show

6- UX issues: Sluggish apps on some TVS/streaming devices

7- On my Chromecast, made by Google, I want my guest to use a guest session on YouTube premium, to not mess up my recommendations, ads start playing. This is the same device, I've not even signed out, just using a guest session.

8- I can keep going on

I understand that license holders play content availability, but the problems above could easily be solved if any of the streaming services cared about their customer satisfaction. I canceled because even when I found something to watch, I never enjoyed the experience. Now I'm an inch away from canceling YouTube premium, and then Spotify.