Furthermore, onchain bitcoin can NEVER be private (as Bitcoin exists today).

Privacy is the selective revealing of information according to one's wishes, and this is not possible in Bitcoin mainnet: source, destination, asset type (BTC) and amounts are ALWAYS visible.

People - even people who should know better - routinely conflate PRIVACY with ANONYMITY.

However, you can never really be anonymous in Bitcoin mainnet either, because addresses are visible.

You can, at best, achieve weak pseudonymity. That is what coinjoins do, and that is why they easily get your account flagged and banned: they reset pseudonymity, but do (and could not do) nothing for PRIVACY, which is how automated systems flag your transaction.

Simple enough - one would think!