With 13% vacancy rate it's most certainly just very marginal businesses that stayed, so rents must be dirt cheap by now. Anything over 10-12% signals oversupply and it's a race to the bottom for landlords. Whatever it is, landlords are not to blame.

People just don't want to walk around places when they can drive and buy everything in one place.

"They do it because they can", this is the best explanation in so many cases, this not the exception.