They fukked up Dorne on the show but, their reasons were legit.
Think about it this way.
20 years ago....Lyanna is "
kidnapped". Brandon gets killed. Lord Rickard gets killed. The North goes to war.
20 years later....Ned gets imprisoned. Gets his head chopped off. The North goes to war.
1 year later....Robb Stark gets killed, his baby gets killed, his wife gets killed, his mom gets killed. The Boltons take over. The North goes to war.
Everytime the Starks got did dirty, they went to war.
But when the Martells lost Elia, Elia's kids and Oberyn, the Lord in Dorne just sat there and said let's think this through
Weak men will never rule in Dorne again and that nikka was weak