Yes, I'm afraid that these kind of scams and problems have become a norm and unfortunately, more and more gamblers have become a victim to some platforms because after having a big winnings, the platform will then initiate their scam and refuse the bettor to withdraw the money they had won. I'm afraid that this problem will be left unsolved because casinos have their own reasons why they did that even if it wasn't really reasonable at all. That is also why we should trust and play to the refutable ones only.
your worries will mean nothing because we can always understand that the casino always wins because they have full rights to what they have and we as customers can do nothing but accept all decisions with disappointment. with this we already understand that it will be very important when we always choose a casino site that has a good reputation and definitely with the most customer trust before sending KYC to that platform. because it will be very important if we choose a big and popular casino at least there is no such action except for cheating customers so there is no problem in the casino refusing a customer's big win.
although this is not a guarantee but at least if we are in a trusted casino we will always be more comfortable with the responsibility of this big casino and don't want its reputation to be destroyed for cheating customers using KYC.