Tartar language is now one of the official state languages of the Crimea. There are now MORE schools teaching in it than before the annexation, Tartars are not repressed in any way. Go visit Crimea yourself and check it. It's not hard, Tartars in Crimea own pretty much all decent restaurants - just go to one of them and ask around.
As for the leaders of Crimean tartars - they are NOT nice people. They supported and encouraged the policy of "land grabs" (or "self-occupation" - "samozakhvat" in Russian and Ukrainian) during the early 2000-s. Groups of Tartars were simply grabbing land (sometimes throwing out everybody who lived there), without regard for any laws or even common decency (like not building on a shared road). Russia is well within its rights to evict more than 100000 Tatars living on self-seized land.