I do agree that it would be better if both abilities were combined into his Leader's ability so that we could get a proper Civ ability.I have no qualms whatsoever with Gilgamesh's inclusion, or even his portrayal in Civ 6 . I can accept historical inaccuracies if it improves my gaming experience; Gilgamesh's characterization is convincing enough and that's what I value most. I do wish "Epic Quest" was his LUA though, with Sumer's CUA being something more befitting for Sumeria (but I Sukhitract saw to that in the steam workshop, so...)
As far as other mythological leaders lots of other people including me are also fine with Dido and Kupe as long as they give us good gameplay.