Imagine apartments built into what used to be department stores, (Oh, you’re JC Penny 203? I’m at Sears 106). Get those old arcades up and running. Set up meal stations at the food court. Once people actually live there, stores will start to move back in.
If I’m unable to finish my life in my own home, that doesn’t sound like a terrible option.
In some places they still make sense. In a place where one can be built relatively close to a number of well off suburbs, while being closer than more urban area commercial districts, malls are still doing alright. The hey day of malls being in every suburb is dead though.