While I do think that bastardy is a significant thing in westeros, I do not agree with your characterization of Daemon and his supporters as a “racist, misogynistic, warmongering faction”.
(Most) Daemon’s supporters hated the Dornish, but it is because they had a long list of grievances and injustices against them. Notice how the majority of Daemon’s supporters were from Reach. There was a lot of blood spilled over the ages, and it had been spilled a lot in recent memory.
To put this in perspective think about Stark vs Lannister in WoFK. Catelyn released Jaime, and Rickard Karstark went nuts. He was absolutely willing to pay with his life to get vengeance. Now imagine how things would have went if Robb married Myrcella and reintegrated with the Iron Throne. Rickard’s sons paid their lives for Robb, and this marriage shows absolute contempt towards their deaths in Robb’s service. How will Rickard feel if Robb or Robb’s son starts giving key offices, positions, and honors to Lannisters? Can you imagine Rickard trying to supplant Robb with Jon because of this? Do you think Rickard feels that he “had the very low-cost option of choosing not to be racist warmongers”?
To be clear, I am not morally equating Robb’s war with Dareon I (and successors) war. But from the POV of Stark and Targ bannermen, they become the same.
TL;DR Daemon’s supporters did not hate Dornish because of racism. They hate the Dornish because of injustices.
Next, the rebellion did not happen because of Dareon’s book-learning. This alone will not breed a rebellion. For example, consider Aerys I. Rebellions against him did not use the justifications that were used against Dareon. Dareon’s inclinations were only such a factor because Daemon offered such a contrast.
The people of westeros greatly glorify chivalry and martial ability. Daemon is such a platonic ideal, that he is compared to Aegon I, Aemon the dragon-knight, and the Warrior(!). And the people believe that “if the king was a good man, the land would prosper.” Are they wrong? Yes. That does not change how axiomatically and subconsciously this belief is held. Dareon can say that the sword is not the kingdom all he wants, but that does not change that *everyone* thinks that chivalry and martial ability makes a good king. Ser Eustace or the Black Dragon side are not the only ones thinking this. Whenever a good martial king is presented in WOIAF, what is the first fact that is mentioned? His martial prowess.
And finally, Dornish are considered culturally other because they are culturally other. The laws of successions are only one example. Food, Climate, Culture, Laws(not just succession) etc. they all were different. And I never once noticed any character saying or thinking that the Dornish are feminine. They resisted Iron Throne rule for the better part of 200 years! They were absolutely willing to go on a warpath after Oberyn’s death. These are a deeply martial people. Doran is the exception. And finally, the peaceful cultures are not really described as feminine. The Lazarene, the Naathi, etc are held in contempt, but they are not called feminine.
In summary, you are trying too hard to fit racism and misogyny into the explanations of the culture. These are very very new concepts, historically speaking. Feudal cultures don’t think like these. The narrative is very much driven by class, legitimacy of kings and lords, control of power and privilege etc.