> How do they update the app if Google doesn't give them
> access to the API? They need to kill it and millions of
> Windows Phone users will be left with no legal YouTube app.
One possible alternative is for Microsoft to release a version of their app that does not violate the YouTube TOS. For example, it wouldn't play videos that the uploader has flagged as being forbidden to mobile devices and wouldn't permit downloading of videos.
There is a public YouTube API, documented at https://developers.google.com/youtube/v3/ , which Microsoft could have used if they were interested in implementing a TOS-compliant app.
To my knowledge the YouTube API doesn't ban users for excessive use of the API, it just throttles them temporarily.
The exact throttling values are not posted publicly, but there are multiple third-party apps using the YouTube APIs successfully, so I expect the limits are high enough for a standard client to work without problems.
There is a public YouTube API, documented at https://developers.google.com/youtube/v3/ , which Microsoft could have used if they were interested in implementing a TOS-compliant app.