A wild guess, but #saltwater might be in there because it contains twat, a nice example of the Scunthorpe problem: https://en.wikipedia.org/wiki/Scunthorpe_problem

First Google result for #hornyyyyyyasf is: https://www.instagram.com/explore/tags/hornyyyyyyasf/

Instagram, you're doing it wrong!

There's probably little human review here. Most likely, hashtags often used on photos reported by users are automatically flagged.

Also why ban only #russianmilf?

#easter and #kansas also seem kind of weird to me.

(And pity the chefs that want to show off their #eggplant parmesean, I guess...)