Personally I trust those entities much more than some shlocky fly-by-night crypto exchange.
To each his own, I guess.
You aren't trusting an exchange when you send a transaction on the blockchain.
This is true, but exchanges have become the de facto on/off ramp for cryptos. If I want to acquire bitcoin without mining, how am I going to do it other than buying from a centralized entity?
Edit: As I post this I remembered that Paradex, a decentralized exchange for ERC20 tokens built on 0x, was recently acquired by Coinbase[1], the largest centralized crypto exchange, who in turn might soon be acquired by Facebook[2]
1. https://www.reuters.com/article/crypto-currencies-coinbase/c... 2. https://www.independent.co.uk/life-style/gadgets-and-tech/ne...
Sure, that's true. But once you own them, they're yours to do with as you please. You can also buy them from someone peer to peer if you really want to onramp in a 'decentralized' way.
Now we're back to no advantage over cash or bartering.
This makes it seem like you can onramp via an exchange and still maintain all the benefits of decentralization. If I don't onramp in a decentralized way then there will also be a centralized entity with tremendous power.