And that dependence was both created artificially and then abused.
Why can't YouTube switch to, say, Azure? Or Oracle Cloud? or whatever other magic exists?
Infrastructure exists outside of Google - as did the ability to decouple Internet Explorer from Windows.
People often misrepresent the MS trial.
I mean it was and still is dependent on MSHTML for rendering things like the help system as well as rich text in many pre-XAML apps. You don’t want the icon on your desktop, fine, but it certainly is a core part of the OSs rendering system.
YT is integrated at every level from infrastructure on up. It depends on Google-internal libraries which are in turn integrated with other parts of the infrastructure... It would pretty much amount to a full from-scratch rewrite of almost the entire product.
Moreover, I'd question whether other providers even have the available public resource capacity to support YT.