Currently I do not see any advantage to do KYC, the idea of this is decentralization and maintain anonymity, the tendency of governments and banks has always been to end anonymity for them to have control.
The only advantage of KYC that I see is for the ICO, IEO projects, which is taken as a protection measure to avoid scams that have fallen so much some investors, however there is the latent risk of using that data for other purposes or worse still sell them .
in general, KYC is used for such things, but many investors do not want to do that, so KYC can only be seen as beneficial from the developer's point of view.