Privacy is everything you do. Your phone/device from the raw chip up to the OS. Privacy is a spectrum from Ted Kaczynski up to Samsung Google phone.
If you never interact with anything or anyone, ever, you have perfect digital privacy.
You'll notice quickly that you don't care about privacy when you have Trust. You only want privacy from those entities you don't trust. Those who run the networks or build the phones or who monitor your financial records and who threaten you for tax income or to enforce other laws.
I don't know if I recommend going through all the trouble for non-KYC Bitcoin, especially meet-ups with strangers. I don't trust them. non-KYC Bitcoin still has privacy leaks if your ISP knows your name or if you're using the non-KYC bitcoin to pay someone, that someone likely knows your name and if they get spied on or captured or corrupted, you're still boned.
If you want privacy from the tax authority trying to implement a wealth-tax, a confiscation of your Bitcoin, non-KYC Bitcoin helps tremendously.
If your local government or criminal affiliates are likely to literally steal from you or kidnap you and disappear you, then non-KYC Bitcoin is important for you.
However, If you want to THEN spend your Bitcoin without leaking your identity to a 3rd party, that's still almost impossible. Any spending to anyone betrays your identity and links it to this Bitcoin, unless its paying for a VPN service or some online only or digital service or product. You'll likely be giving them an address at least, if its not digital/online only.
The best privacy you can have in Bitcoin is both non-KYC Bitcoin and good UTXO management in order keep differently sourced Bitcoin in separate outputs so anytime you link yourself to these UTXO, by spending and receiving real physical goods or services at your actual location in real life, you're only linking a small amount of Bitcoin to your identity.
However, its really not possible to spend Bitcoin and remain anonymous. Even if the exchanges didn't need KYC. Someone would still know something and good ol' fashioned police work and parsing through logs and testimonies, would reveal you in some chain of transactions.
