Here are some examples: https://johnaugust.com/2018/missing-movies
Here are some examples: https://johnaugust.com/2018/missing-movies
Interesting side note: a couple of years back, I wanted to buy The Abyss on blu-ray. When I went to look, all I could find were DVD versions and a crappy fake blu-ray version where someone had just ripped a DVD and transferred it to blu-ray (seriously).
After a bit of digging, I came to find out that there is no blu-ray version of The Abyss because (basically) Cameron has been holding it up. I don't recall the exact details, but it has something to do with him wanting to oversee it personally, yet simultaneously never bothering to actually bother to get it done.
Looked again just now and supposedly the work has finally been done (?) and it was to be available last month, yet as of right now it's not available on amazon, so who knows..
Highly recommend the documentary about shooting the film if you're a fan[1]. It's a film that could never be made in the same way today. The rat breathing an oxygen rich liquid scene was real (not saying this is a good thing) and the stuntwork of actors was even more dangerous.
Is it though? To me, it seems much more to the whim of the content owners. If they choose to not make it available to the streamers, then it's not the streamer's fault for not having it.
I do agree that it's related and that it will likely lead to a similar outcome where new things get lost permanently.