I agree with you. It's one of the reasons i feel P2P will be the future as people gradually start to remember that Bitcoin and Cryptocurrency were always meant to be and are inherently P2P.
Even if totally P2P, centralized exchanges do something way better than general p2p. For example, what use do I give to crypto? I get paid in crypto and sell to send money to my parents in my home country, not being from a first world country, finding people that buy bitcoin with my home countries's currency is pretty difficult, and decentralized exchanges really go after main FIATs. So in my particular case I find use in centralized exchanges, at least until a more decentralized option makes my home country's currency as one of the escrow-able options.