Today there are those using P2P sites where you can pay in cash, or using gift cards or other means that are less trackable, but even in such cases, impossible to say you are being fully anonymous. Other people make use of cash-accepting Bitcoin ATMs, which may also have limits and necessitate a form of identification depending on the location. Much of the anonymity lies in your abilities to be cautious of your trades and the means you employ. Shortly, as you attempt to extensively combine fiat and crypto, the less anonymously you can remain. It is about convenience, privacy, and legality.