Looking at things pragmatically widespread education of the population takes time and simply won't take for some people. There are folks today complaining that "they don't teach taxes in school". These people have a problem filling out a 1040EZ. Not exactly encouraging.

At the same time Tic Tok represents a single vector for current or potential foreign propaganda and intelligence gathering targeting the American public. Opportunities to nip a single bud (so to speak) are few and far between and probably won't be possible in the near future.

TL;DR - The "sell or ban" is a short term measure that won't take a lot of time, education is a long term measure that takes years.