TL;DR: Some folks still don't know that it's hateful due to being told and taught garbage, but more people know and understand every day.

Not always true, although it's probably more true today than it was back when I was growing up and someone outside of the southern bubble flying it definitely knows better.

The insane amount of misinformation given to kids in the southern US is pretty crazy. We learned "states rights" in school (before the internet). The iconography is everywhere. We had schools either named after Confederate generals (Robert E. Lee) or with Confederate iconography as part of their identity (the Rebels, which used to be complete with a Confederate soldier mascot). One of the shows that everyone watched featured a car named after the aforementioned general and was painted up with the stars and bars.

A lot of these folks have never been more than two hours from their house and are in little bubbles that tell them the crazy leftists are coming to take away their weiners. They absolutely do not know better because they grew up with it being glorified.

I got really lucky. I learned a lot when I got out of that hellhole. I understand how my actions affect others and know why that's a hateful symbol. But I can say with certainty that some of those folks absolutely do not know and really think it's just about the rebellious spirit of the South fighting against an incompetent and corrupt government. That doesn't excuse it, but I hope it does explain it.

Luckily, as I mentioned at the beginning, that's changing. People who are younger than me grew up with a more digital life and a lot of them never adopted the "rebel" lifestyle. They understand that it's wrong and, more importantly, WHY it's wrong. That tide is still turning and I'm here for it.