It'll keep continuing until you get one FPS and no audio without paying for premium.
He doesnt get a benefit afaik. Its automated by YouTube, some (1080p) videos get it, some dont. Thats why is might look shit, this creator just has a worse setup now and isnt encoding his videos with a good enough bitrate. If YouTube think your video will benefit from more bitrate, then it transcodes in a higher bitrate, if it doesnt, then that enhanced option doesnt even appear.