I looked in vain for a link or some small print on the rotten tomatoes website regarding how they calculate "popularity", as it clearly does not correspond in any way to actual viewership numbers.

I found absolutely nothing.

They most likely use a metric which measures social media engagement, but if you actually go to the #RenewTheAcolyte threads on Twitter, you'll find that 9 out of 10 comments are mockery and memes about how truly goddess-awful the show is, thus amplifying its "engagement" by an order of magnitude, precisely because of how universally loathed the show is.

So apparently somebody needs to break the news to rotten tomatoes that "popularity" does not mean what they think it means.