Why not? There was a point in time where everyone knew nothing about Tor, VPNs, coin mixers, etc. It doesn't take much time or effort to gain a working knowledge of these things. Why are you even asking questions regarding your security and privacy if you have already resigned yourself to never bothering to learn?

You're right on the second part.

Coinbase are shady as hell. They openly admitted that they hand out customers' details to third parties for "processing", and that some of these third parties share and sell that data with even more third parties, all without their users' knowledge and consent. They hand over customers' data to the government. They formed a partnership with a company who produce and sell privacy invading software to dictatorships and human rights abusers. I wouldn't trust them with a single satoshi, let alone all my personal details.

Pretty much this. I trade exclusively peer-to-peer, and pay less in fees than I would on a centralized exchange. Often I'm trading with people I've traded with before and trust, or if I'm trading on the forum, then the only fee I'm paying is a transaction fee of a few sats per vbyte.