Insurance is required in all of Michigan, with fines, license suspension, and jail all possible for not having it. With Michigan's no-fault insurance we have some of the highest rates in the country in Detroit—especially relative to income—and almost no viable alternative to owning a car.
That said, as a native Detroiter I feel safer in Detroit driving around other Detroiters, the suburbanites and out of state folks are always in the way.
Those are some of the first below-grade expressways built in the country, so the shorter on ramps are from an era with fewer and slower cars, and there isn't space to lengthen them. The law only changed to stop the insurance companies from using zip codes to determine rates, and reduced the maximum payout for healthcare related costs from a crash, with the aim of lowering costs, but of course the insurance companies worked around it.