All Bitcoin transactions can be seen on the blockchain and be tracked from the person who bought or sold on a KYC exchange.
That's if you wanted it that way or wben not conscious of your privacy, there are many ways you can stay off the implication in KYC challenges when you don't deal with centralized exchanges, also your transactions can be seen by everyone on the distributed ledger but no one can alter it, but to remain more private you can run a full node transaction on the blockchain.
imagine every single person being able to see how the governments / politicians really spend tax money, you’ll be able to see everything on the blockchain!
This can only occur if the user is not privacy concious as I've said earlier, if you know what you're doing then you shouldn't be abke to be tracked down, you only see the receiving addresses for the transactions but hiw do you know what the transaction is meant for? No how .