I think that me going to Catholic schools, including a Jesuit school, somewhat insulated me from that. Not that I didn't see/experience racism and such - dude, it was Texas in the 70s-80s -- but because in my tighter circle, it not only wasn't tolerated, it was expressly taught AGAINST. My handful of classmates who were more openly racist actually stood out. And, we had scholarship students, and minorities, and they were generally treated well and well-regarded (again, sure, there was a divide between the really rich and snooty and the rest of us, but that was asshole-based, not race-based). So, as much as I was exposed to the full world, had family on both sides of the border, grew up among oilpatch types, etc., I was also pretty sheltered, and not only was I not really exposed to the worst impulses of the GOP, I was actively indoctrinated against them, by many people who were also Republicans. I was sheltered, had a small sample-size, etc.
When I got to UT, I got to see more of the broad entitled rich white kid dynamic, and it did indeed start to open my eyes.
And let's not forget that the Republican party in Texas actually pushed back against some of this nativist shit. I actually remember a meeting back when GWB was governor, and a guy showed up with a whole anti-immigrant screed (that would be moderate in MAGA world today). He was told to GTFO, in pretty plain terms. BUT, the precinct chair explained to me that those assholes had started showing up a few years back, and they were going to keep coming back. He was right.