Not to mention they spent most of last season hammering home that a bastard, even if legitimized, isn't going to be respected enough to rule without marrying a powerful house - hence Ramsay and Sansa. And then tonight a bastard kills the Dornish Prince as his guards cosign it, and will presumably be ruling Dorne now.
Like literally, the entire (show) Martell line was eliminated by some bastards and Dorne is cool with that, because they want revenge...for Elia Martell and her children. Wut.