As for the KYC part many members are commenting on, this probably is a legal requirement from the providers. Most of the brands I'm seeing like Betsoft and Evolution hold multiple licenses (MGA, UKGC, etc.) that demand they verify players. These are all measures to prevent money laundering and underage gambling they must comply with. So, I'm guessing it wasn't Bitsler's choice.
In fact there are still many crypto casinos that provides the same 3rd party providers but they do not ask their players for KYC just to play the games. Of course there must be a valid reason why Bitsler decide to make KYC is mandatory for their players in order to play those 3rd party games but I can say that it can be a disadvantage because there are still many crypto players who wants to play anonymously.