Right. I haven't been able to actually do my own testing for life reasons, but I think it matters less what the actual numbers are here, and more that the guy stopped posting free 4k versions once the paid 1080p option came out; basically cutting his quality down in the name of, whatever benefit he gets from the paid 1080p thing.

In short, YouTube added a paid feature that encouraged the use of a shittier quality unpaid user experience. Worse, because it appears to be a choice on the creators side, instead of YouTube or the viewer, it shifts blame from YouTube, who created the situation in the first place, to the creator, who only took advantage of it (or used it because this is their job and they need the money to live).