All exchangers at Bestchange that have KYC do so. That's the point. And Bestchange keeps them there, disputes become gray and admin says everything is ok.
BestChange needs competition. There's
KYC? Not me!, but it still lists several of the same exchangers and doesn't have the marketing budget to promote it.
Some anonymous guy says "well, I think your funds are from bad origins so I'll seize them and will keep them, bye, thanks"
It was suggested before that someone creates their own "Taint detection service", that just labels every address as clean. After all, that's how Bitcoin and fungibility works.