Lots of "real" downtowns are also intentional -- they are just the product of zoning and lobbying by local businesses. That something has been designed doesn't make it fake. Places with dense population are attractive for shops, places with good shop access are attractive to live in, and there's a feedback loop there. The degree to which that feedback loop has been spurred on intentionally sits on a spectrum.
For example if the apartment were entirely for show (not actually lived in) I would call that fake.
I think it's a great idea. There are plenty of working examples of housing/retail where people never have to leave indoors to get all their basic needs taken care of.
There's of course megamalls out by me as well, which are doing just fine and don't need to evolve. One is in a wealthy suburb, and has a shopping tourism industry which props up the local hotels on the weekends when business travel is low.