But I've passed KYC on Binance just to be sure to have some instrument that my account is mine.
This is a poor reason to complete KYC. If you have different, strong passwords for both your email and your Binance account and use a secure method of 2FA for both (not SMS or SIM based), as well as practicing basic security practices such as not logging in on public computers, then the chances of your accounts being hacked are minimal. If your Binance account was hacked, then you should be able to recover it from your email address.
If your account was hacked, and any coins you had on it stolen (although they shouldn't be since you should be storing all your coins in your own wallet), then what good is recovering the account anyway? You won't get your coins back. Risking your KYC documents for this reason is pointless.
I've got your idea. Maybe passing KYC on Binance was not the best idea after all. But what about situation when your mobile with 2FA is stolen. How can you recover access to your account ?
Anyway, I will never pass a KYC for a bounty reward or something that I wont use often.