My son is a fan of an old TV series – American Loggers. When we recently restored his phone from iCloud backup it was missing.
It’s no longer available in the US:

We did have copies on iTunes, but not all of our media is in iTunes now. Some movies and TV shows are iCloud only. Those could vanish at any time, even though we paid for them with the expectation of long term ownership.
The not-so-long-term fix is everything streaming/rental, no expectation of ownership. It will become much harder to access and use the media we purchased in the past. I’ve already found that synching an iPhone with both iTunes and iCloud media is very problematic. Apple must know this…