Great post.
Are there any other options outside of just staying off of exchanges/avoid KYC. Any resources or articles to better protect your privacy while using BTC?
Use Tor, use mixers, use Bitcoin Core. Important to note that your privacy leak may or may not be related with Bitcoin.
No such thing as anonymity in Bitcoin, even if the users were to be careful with their activities, it would be the best to assume that Bitcoin is pseudonymous at best. There are far too many possible privacy leaks with users even if they were careful enough; potential spy nodes on the network, possible leaks through mixers with their heuristics, etc. Bitcoin was never really designed to provide anonymity from the start and all the current implementation only helps to maintain the privacy of the user.
As mentioned, CoinJoin, mixers all helps with the privacy. Confidential transactions has been proposed as well, which helps with privacy but at the expense of higher resource requirements.
What is the main argument by the community not to provide an additional layer of privacy onto Bitcoin? There've been scaling improvements, fee cost improvements, and some small privacy improvements (coming soon). I assume the technology is available to add additional privacy to the protocol through zk proofs or something of the like.