I don't see much future for this scam accusation from what the OP says, You can question the way they operate, but they are not a scam.
Looking at the other thread, I see that what happens is that the exchange freezed the funds that passed via Chip Mixer, which brings us to the central issue that is being discussed lately in the forum:
Unfortunately, BestChange supports the anti-Bitcoin idea of "taint", and like most (or all) companies that do so, they don't state that on their website.
Leaving aside the unfairness of this, do you see much future for a business model that is dedicated to obscure the origin of funds for "privacy"? I see it as having the same future as crypto ATMs that let you withdraw tens of thousands of non-kyc Euros in a relatively short time "for privacy".
Comprare/Vendere Bitcoin senza KYC: Bancomat Bitcoin rispettosi della Privacy Translated: Buying/Selling Bitcoin without KYC: Privacy-Friendly Bitcoin ATMs.
As of today they require KYC for any transaction, any amount.
I believe that politicians are not aware of what mixers are, otherwise they would be banned or forced to operate differently, like ATMs.