Not people jumping to blame DAEMON'S influence for Jace calling bastards "mongrels." When has Daemon EVER been bastardphobic? His attitudes towards Jace's parentage include some possible jealousy while he and Laena were both being good natured about it, seeming kind of proud of Rhaenyra when she admitted it, seeming pretty enthusiastic about wedding his daughters to "bastards", and literally killing a man for insulting Rhaenyra and her boys. I just simply don't get where this "Daemon is a blood supremacist" (more than any other noble is) comes from when he gives no fuck aside from jealousy about Rhaenyra "sullying" their Valyrian blood with Strong blood and putting her bastards on their precious dragons. Alicent is the most likely source of Jace's internalized insecurities (because that's what that was) so why do people keep pretending otherwise? Am I missing something?
I think that it's an opportunity to slam Targs, use the less-than-great reputation Daemon has amongst some fans--which includes his supposed "special" pride, and finally to incorporate Jacaerys into that to "prove" Targ-evil and unique amorality. That is pretty much all, aside from how Condal & co have written their version of a Jace to be less secure in himself and have less...I guess "family" as its truest phenomenon. Again, Daemon lived w/Rhaenyra her her co on Dragonstone for abt 1o or a little more with both Baela & Rhaena. Before that, it had been Harwin with occasional & then more frequent visits from Laenor. He more or less grew up away from the court Alicent presided even as he experienced some of the stigma of being even suspected as a bastard, esp from Alicent's supporters, here & there. But more so from his uncles: Aegon, Aemond, perhaps Daeron, too who'd follow his older brothers.
I also think it's bc Daemon has a lot of pride in his house that they are bound to think are white supremacists/colonizers and has disliked Rhea Royce from the beginning while being more amenable to Laena and Rhaenyra, who are both much more Valyrian-by-lineage than Rhea, who has none. Nobles are engrossed in making sure their marriages afford them the best possible access to resources and the prestige associated to whatever house so that they may have issue who can brings usch things into the "home" house or out to the house(s) chosen and favored. It's a way to organize wealth and power. Targs on Valyria and the rest of Valyria saw strength in their dragons, the pinnacle of such power matter of fact. So--as they too, maybe, didn't have that much knowledge about genetics work outside of the magic that in Planetos is more unpredictable than other magical systems--they decided that to preserve their power/dragon bonds, they must do as many other aristocracies did--marry closely and keep that line towards power amongst themselves. I said all of this before, but it bears repeating. Daemon & the Westerosi ruling Targs , however, has never gone out of their way to create a racist system except maybe Daeron I with Dorne if he had ever succeeded in conquering it (in which case, the Dornish are not nonwhite in GRRM's lore, so that racial system would not really mirror out own very well and be its own thing entirely).
Daemon has never even displayed true blood purity the way Alicent was closer to in 1x06 when she commented on how she called them "plain-featured" and groused abt how she couldn't understand how they could have hatched their dragons...while 3 of her kids had to wait till they were much older to bond with one. Daemon never called anyone anything that espoused he thought them as lesser in the exact degree or way that Lord Celtigar does in I think 2x06? 7? (I recently ___ epi 7 and watched w/ a few friends) when he protested against Alyn getting a dragon and even called it "theft". And we see in how he interacts with Alys how he was never actually blood purist with her...an actual unrelated bastard. Daemon just cares about whether you can be trusted to not supplant family, and the Targtowers are too mired in Seven/Faith influence to be "trustworthy".
It also stems from people not truly understanding what blood purity is & its elements or what it looks like when practiced and in the open, active. You hear people make the mistake of assuming the Targs are all blood purists bc they dislike how "keeping the blood pure" thru sibling marriage for dragonriding sounds to them like the Valyrians were ready for phrenology and eugenics and all that...If this were true, however, every single society (or at least most)--and that includes many non-white societies like the Egyptians, some Polynesians, East Asians, etc. as that particular kind of "blood purists". I list of these out bc you will find such "keeping blood pure" practices in nonwhite ancient societies as well. Often. Class=/= race, though it definitely laid the frames for race as we know it; racial systems have inherited ideas of racial difference from class assumptions of difference b/t aristocratic classes and the have-nots. To put it oversimply.
Still, they are not the same. Or we wouldn't have "white" people of real life AND Westeros also hate or abuse the other in their systems. If the Westerosi ruling Targs were that sort of "blood purists", they would have never allowed themselves to marry outside of their own family for fear of "dirtying" their "blood", or lineage. And they, more than the Starks, have had quite a diverse set of outer marriages through their entire dynasty.
I think Daemon just has a lot more expressed pride and arrogance that puts people off and leads them to make wrong, well-meaning conclusions. Oh, & of course HotD hasn't helped, with how they reduced his character at every turn possible.