exchange security or kyc will be exchange's policy. They need customer personal data in order to record money flow if something wrong happen. For example if exchanges hacked ,they could track this fund run to which people and block address to avoid massive dumping . Personally i am comfort with this policy. It give me certainity and comfortable. Unfortunately many traders didn't understand about it.
For you to make sure that your funds is safe or your asset, make sure you only trade on a real exchanges and top exchanges like binance,hitbtc,livecoin,bibox and so many more, you may see it in coinmarketcap list of top 10 exchanges. It is good to know that these exchanges having a great security that it is too hard for the hacker to control, it makes our worries gone and our assets safe. But you need also to strenghten your password security.
Crypto exchange still the safest way to buy bitcoin but make sure that the exchange that you will use is belong to the highest daily volume and have high security. Do not buy in ecommerce platform like eBay because there is high possibility that you will get scam. There are also online wallets that you can use like coinbase and coins.ph to purchase bitcoin.