Again, depends on the amount of money. Sure, there is not gonna be a lot of action from the IRS or any other government entities for $2 million. But when we're talking about $100 million, you start to ruffle some bushes. So they will start to dig where it comes from. If you describe that you got $100 million from mining Monero, you're gonna have to show proof that you have the equipment to actually get that, over the timeframe you're claiming you have mined. If it doesn't match up, they'll dig deeper.

But yeah, I'm not claiming it's impossible to clean stolen ETH. The only claim I did was that the IRS will definitely start asking questions if you go from a declared income around average in the US to a declared income around $100 million from one year to another. To believe that they are just gonna accept "I mined it lol" is a grand delusion.