Google warns users of these apps that their experience may deteriorate soon. They may "experience buffering issues" or see errors such as "the following content is not available on this app" when trying to watch videos.
Similar to Google Search, ads have become insufferable for many users of the service. There are too many of them, they may break the viewing experience, and they may show inappropriate content.
YouTube Premium is expensive. What weights more for some users is that its functionality is severely limited when compared to third-party apps.
The cat and mouse game continues.
For those looking to avoid ads or improve privacy, here are some options for free, open source, privacy-friendly frontends to YouTube without advertisements:
https://www.privacyguides.org/en/frontends/#youtube