You could use monero in P2P transactions, but any registered exchange will get pressure from governments, complaining does not gain exchanges support. Over the last decade, localbitcoins (where I had over 100k P2P transactions with real people) first bowed to regulators and sharpened their KYC measures, and eventually they had to close the shop due to threaten of law enforcement action. Same goes for localcryptos (former localethereum).
Besides, if you are selling coins and never do KYC check, most of the time you will receive fiat money from an illegal source, typically a scammed or hacked old lady. I have lost most of my bank accounts due to not doing KYC in early days. KYC is just a way to make the scams/hacks more difficult, and leave trace for possible police investigation, it is not a requirement before 1970s, but then we did not have modern electronic banking
Many fake assumptions here, not least that you have not accounted for surveillance capitalism.
KYC is the demand, not only to collect data but to share it
without your consent to whoever, whenever and however they want.
KYC laws make it
illegal to delete data for many years, and sometimes forever.
KYC is also, almost always, personal biometric data e.g. high resolution photos where medical data may be extracted today or in the future. Think DNA and how it evolved. Your photos of today will be used against you, diagnosing disease without informing you at the earliest possibly time. Or perhaps an AI rating the likelihood of you committing a crime.
Financial regulation is deliberately vague, that financial institutions over compensate on their KYC policies or face fines.
The more demands made of KYC, the more costly it is to maintain. Those costs are passed on to customers whom are by-and-large innocent bystanders.
What is legal in your country may be illegal in a different country and vice versa. What is legal today may become illegal tomorrow. KYC doesn't make the laws but it is the poisonous instrument to uphold it. And, in any event, KYC is also used to punish people who do not abide by an institutions moral values e.g.
sex workers being banned at exchanges.
If you truly believe you are innocent until proven guilty, you would not defend KYC, you would demand a genuine belief that a crime has been committed, then you would collect data to make your case.
I reject your claim that most of the time, selling coins will receive fiat from illegal sources. You must weigh this against the theft of time and energy to produce work and then have it stolen via taxes and inflation. Taxes that fund wars for which I never wanted.