I personally prefer KYC at the beginning rather than having to KYC after wanting to withdraw big wins, it will be more complicated.
but i do KYC early usually at a reputable casino here and Rollbit one of the good reputable casino. so you don't hesitate to do KYC at the beginning and are more comfortable when you are going to withdraw large funds without asking for KYC again.
It's rare to find players who want to do KYC at the beginning, especially when registration is not directed to be required to do so and also sometimes casinos include KYC not as a requirement except in certain circumstances such as large deposits and large withdrawals or when there are suspicions that arise, I prefer not to do KYC if it is possible but if it is a must then there is no other choice but to comply.