The last stats I saw had Shadowheart and Gale at #1 and #2. Astarion does seem to get more attention in the online spaces.
Those stats were right after full release. Gale's romance was triggering for people who didn't want it. It was the first noticeable glitch in the romance system. The only reason so many folks "romanced" Gale was because they didn't know they were romancing Gale and subsequently got annoyed by it.
