but no issue until you cash it out. if we make cash out impossible to detect the world governments will go after btc like mad.
Something is wrong here. Why do you speak of “cashing out” in the context of mining?
Mining is only an indirect way to cash out your central bank shitcoins to money, i.e. Bitcoin: Pay electricity costs directly in $hitcoins, receive money. But it is not as anonymous as you suppose: High electricity usage is very difficult to conceal. Many people doing illegal stuff with high electric draw (e.g., clandestine indoor marijuana growing) have been caught this way.
If you have anonymous dollars, there are more private ways to cash out to Bitcoin.