Most of the business which are in money laundering are no longer using these Mixers. They have much better options to use rather using Bitcoin. They can simply buy XMR (Monero) and use that as it's a private blockchain. No transaction can be tracked. And then you can even use Monero to then get it converted into real fiat money. And yes, that's true. Mixers alone are no longer suitable for money laundering.
Mixers are old school, I don't even know why you want to risk tainting your coins in there when Monero does the job for you at a much more efficient way and less hassle because it's pretty straightforward since it's just like any crypto albeit much more private.
Let's say 1 Billion happened via mixing what about the remaining 799 Billions? How long the government can blame the cryptocurrency for the incompetence of AML?
As long as it benefits them, they will blame cryptocurrency or better yet they will continue to use cryptocurrency as a scapegoat for their incompetences because it's that easy to blame it compared to taking responsibility in their incompetence, this shouldn't be any surprise to you since you've been in crypto space for a long time already.