It seems that the KYC is a must now for TrueFlip users as what informed on the AML/KCY policy page. The reasons are actually common thing, related to money laundering and terrorism financing. To be honest, IMO it should not be applied to all users. It is better if the KYC applies for users who are suspected to do such criminal things.
KYCs is must thing to do nowadays, to prevent monely flows to bad forces, like terrorism groups.
Of course, it is clearly that KYCs often raise worriness about risks of leaks of personal information, data hacks/ leaks, risks of losing money due to hacks.
However, in general, KYCs is not too bad ideas to control and prevent bad forces collecting financial sources for their operations, that is only bad for the world.
Not all gambling sites requires KYC, they would only require in rare cases like if their customer is under investigation and they freeze the funds.
You should know the site you are playing, their TOS, so you will not complain, this site requires KYC and therefore you comply.
I have played in different gambling sites and I feel comfortable playing anonymous but that depends to you.