I am not I full support of doing KYC up-front immediately you register on the site, and reason being that, you have to check to know how long you will be playing on such a casino, because you may get fad up with their services the moment you start playing on them, so if you do you front KYC at that point it could become a waste of time , but if you have played there for a while and accept their terms and conditions and patterns of service you will be ok to go through kyc or not depending on what the urgency for the KYC is.
People need to quickly search about reputation of a site first. Like searching as "Is Binance scam exchange". If you get result as "Binance is a scam exchange", it is warning for you to be more careful but you will need to search more to be sure that it is actually scam.
If searching shows that it's not likely a scam site, you can continue with scanning and skimming their FAQs and ToS for finding more information. Assume that you already see interesting services and products from that site, which you want to use, then finding basic important information in FAQs and ToS is next important step.
After all, if you want to use that platform, and there is rule on KYC, doing KYC before depositing money is good practice. I dislike KYC but if there is KYC requirement, I will not risk my money by deposit first, KYC later.