Are you seriously gonna believe your KYC info there is perfectly safe and secure? Once their system been jeopardized, and you know hacks and data breaches happened regularly in the crypto space, your identification is gonna be listed for sale at $1 or less on some dark web market. In one week you will receive a court warrant for some crimes you did not commit in places you've never been.
That why I only stick to no-KYC exchanges: Coinex for spot trading, and BaseFEX for margin trading.
For the sake of launching financial affairs in trading, I am still willing to do KYC, except on the bounty or airdrop site I will never do it.
The use of KYC in trading is not much different from the purpose of KYC in banking. So, in the KYC trading also aims to provide security for the user, and the market itself also oversees trading transactions, minimizing fake accounts that can lead to cybercrime.