Day in day out there are new projects requiring kyc from investors
Exchanges requiring kyc, for some in order to maximize your ability to withraw large sums of cryptocurrencies and some even before you can trade on the exchange
The bigger question is how safe are our kyc documents?
There is no way to know if your KYC details will be safe in the hands of exchanges, those who owns exchanges are humans too and anything can happen, instead of taking the risk it will be better to get used to DEX exchanges or find some exchanges that doesn't require any KYC details for trading or exchanging coins and tokens