Yeah, they are not explicitly saying "Tesla" in the law, but everyone understand it's anti-tesla bill. (Exactly like the anti-uber bills in some cities that are generic but target Uber.)
It's not a law targeting Tesla. The law predates Tesla.
They could easily add an exception for companies that don't distribute through dealership(which has happened in other states) but I doubt you'll see it any time soon.
The TechCrunch article mentions a recent law:
"The state’s governor signed a law last October that banned the company from selling its vehicles directly to consumers."
My bad. I somehow read it as a case last year, not a new law.
In a lot of states (not sure about Michigan specifically), the law was "if you have any dealers in the state, you can't sell direct". The dealers are trying to change that to "you can't sell direct" to block Tesla.