One accident was a Yugo that was blown over the side by a gust from below the open deck part of the bridge.
Last time I crossed there were 35mph gusts and they had the speed limit down to around 25mph.
The open deck is a necessity that came as a result of the galloping bridge in Washington state that collapsed in the 40s.
The Mackinaw bridge is definitely one of America's top 5 engineering/construction accomplishments. Its one that doesn't get the appreciation it deserves because it almost has to be your destination in order to see it. From anywhere north of Lansing Michigan, the northern route to Wisconsin is really the faster route.
Not quite a bridge to nowhere, but I agree that it is more of a destination than a pathway. Personally have been over it a few times, and also under it twice. Once eastbound, once westbound, sailing from Charlevoix to/from Mackinac Island.
Actually, I have been over it an odd number of times, having driven from Denver to southern Indiana by way of Duluth and Mackinac in the late 70’s.