The only way to have anonymity is to make the entire network anonymous. Having any transactions open means that the chain can be strung together.
Besides, at least in the US, everyone gets onto the crypto highway with full identification which establishes the starting point of all transactions.
If you know what you are doing; you buy from anonymous parties...
That is true....although many, especially newer people. start with the Coinbases of the world.
Although the stability does provide them a bit of safety albeit at an expensive price.
There are also mix master exchanges, and it makes anonymous usage possible.
I intend to find a good one soon...