Regarding handing out your KYC documents upfront at the time of registration, IMO, it is a very good idea, but there is no guarantee that pro-KYC casinos will not ask for additional documents. So all in all, if you are playing at reputable casinos and not cheating, you will enjoy a good experience.
This is always a bad idea anywhere. KYC must be submitted only at legit sites when deemed necessary since it goes against everything BTC and crypto in general stands for which is why I disagree here.
No one can guarantee that a reputed site will not request KYC repeatedly just because you submit them initially and don't cheat. Just look at what an elite site like Binance is doing for example.