Actually, I don't think it's really a matter of good or bad, because both things are happening at the same time. There's a lot of people genuinely interested in learning and sharing the culture, but there's also tons of creators who just take the dance, strip it of context, simplify it to make the trend go viral, and then it becomes this hollow thing. The real risk is that younger people end up only knowing the TikTok version of the dance, without understanding the history, the cultural significance, where it actually comes from.
It'd be cool if it served as an entry point and people dug deeper afterward, like your grandma did when she found it interesting. But that doesn't always happen - it just becomes another meme that nobody remembers by next week.