The real question is why does 95 percent of the player base only get one romance option "Shadowheart"?
I think you misspelled "Minthara". :P
Gale's popularity surprised me, because everyone is talking about Astarion and he's really easy to get. Getting Gale's romance is not so easy, which is worth its "rare" cutscene, which I still haven't been able to open. Gale also has a "love past" that is actually unpleasant. Wyll, too.
Funny ...
I see it exactly otherwise.
Well maybe not exactly, since i havent seen Gale's romance, unless i specificly aimed for it, that is true ... but it was exactly same for me with Astarion, or Shadowheart. :-/
Wyll seemed like freebee, just like Minthara ... help/burn the groove and here you got your lover ... i rejected him every single time tho, since he is just awfull person. -_-
So, for myself ... the best Romance option was allways Lae'zel (unless Minthara happened).