it's logical since no one would really try playing on a casino that request a KYC up front.
This isn't accurate since many gamblers play at popular sites like Roobet, Stake etc who mandatorily enforce KYC since they trust those sites completely. Some gamblers provide fake KYC in these sites which is a risky approach.
Mandatory KYC(Any Level) sucks regardless of how popular the site is in my honest opinion.
I don't think that casinos or any platform ask their players or customers to complete KYC verification because they like to do it, but they do it because it is enforced by the regulatory bodies that issue licenses to these platforms, so they are basically compelled to make it mandatory for customers to complete KYC verification before they can access all the features of the platform including withdrawals which is the most important thing in my opinion.
So we shouldn't really blame the platforms for imposing KYC and making it mandatory, we know that a lot of gamblers leave a certain platform only because it requires KYC and I don't think any business would like that but they are compelled to comply with the AML rules.