They are definitely A/B testing ad tolerance.

I reset the TV app whenever the ads become unreasonable, and every time I do that, the skip ads button reverts back to the original style (skip all ads after 5 seconds).

But if I login to an account, or use an anonymous session for long enough, the skip ads button will switch to the progress ring style, with 60+ seconds of unskippable ads. When that happens, I reset the app again.