Why do you think Instagram is immune from being used in social media based campaign? The only difference between TikTok and Instagram is the recommendation engine they use
This specific campaign was done via TikTok, though, and had massive impact, which shows that TikTok has heavy usage and is popular, outside of the US and China.
(I'm not American, I have no horse in this "ban foreign TikTok" race. :D)
Why they've done it via TikTok - I simply don't know. :D
Maybe better discoverability via the For You page?
maybe next Christmas if I'm not on the Santa naughty list