Something like this seems so obvious to me since I don't drive thus tend to see cities on a slower, more intimate level. Rust Wire has a speculation that the core problem with Cleveland's downtown comes from the vast area dedicated to surface parking lots. (As well as atractive but large, "keep off the grass" parks.)
Comparing aerial views of Cleveland and much more successful downtown like Toronto shows just how much space is dedicated to cars.
I'll be really honest, when I visited Cleveland, we pretty much drove everywhere in the downtown. It just wasn't nice to walk.
If this theory is sound, it means that the huge single use venues like football stadiums not only deplete tax dollars, but create masses of parking that subtract life from the city when (95%of the time) they are not used.