I probably wouldn't call somebody "a popular creator on Tapas" unless they had about 10,000 subs on Tapas, even if they were pretty popular elsewhere.
As good example, Theorah's most popular work, The Pauper's Prince, has a similar sort of following size to my comic, but Theorah has a pretty big following outside of Tapas, with a recently published print comic called "Speak Up!" and a lot of visibility in the Autistic community (like some famous mini comics about the Autism spectrum). So they're not necessarily huge on Tapas, but they're still a popular creator in other places.
10k subs is the point where seeing a comic, or especially a novel, I stop and go "Oh, wow, okay, those are some serious numbers. This person is killing it at Tapas."