Have no info on sales but can tel you this,
I have spend around 280 dollars on Unreal store this year and around 140 dollars on regular assets (kitbash sets, brushes, shaders, reference materials, etc.) on ArtStation and Gumroad, then later found out some of the content was also available here on CGt.
The thing is, on ArtStation I follow a bunch of artists that create great content (including Unreal content). Most often I get seduced into buying things when one of these artist has published something new and I get notification about it via email. Sadly this is missing on CGt and that’s probably main reason why I never was successfully seduced into buying something here (so far).
Those artists just got faster to me and provided link to Unreal store or Gumroad.
I'm sort of an opportunistic purchaser, not easy to seduce but when the right thing comes in my view, I just get it right there on the spot. I’m probably not the only one that rely less on search and keywords to find the best artists that deliver the interesting stuff?
Also note, Unreal store is well integrated with the Engine, so you can import the purchased goods directly into a project with a push of a button (and its curated content).
I’m telling this to point out there are different types of buyers and different types of stock markets having different types of sales tactics. Some approaches work better to get to the types of buyers like me, other approaches work better to get to (probably call it?) the mainstream.
Looking at it that way, its probably wise to be on the mainstream platforms but also be on the specialized (if your stuff is indeed more specialized).
