What you're writing makes a lot of sense to me as a non-American where car culture is much less strong. I think that the US currently is undergoing a shift towards less car usage, replacing some of it with delivery services, home offices, more central living and public transport. There are still strong forces that counter this movement in the US, namely the way overregulated metropolitan housing market (compared to Japan or even Europe) and the political difficulties and ballooned cost of public infrastructure, but nonetheless the shift is happening albeit slowly

What does this mean for malls? Just look abroad. We do have malls, just smaller ones that you drive 30min to at the maximum, after that the added value becomes too weak. Japan kinda shows the endgame, with malls fully integrated in many train stations, so you can go for some shopping with minimal loss of time. Amazon is extremely strong in Japan, with same-day delivery for prime members, yet this doesn't seem to affect the more upscale malls that you describe much. Specialised stores for electronics or clothing meanwhile compete mainly on service, in some areas also on price (Amazon does have quite a different cost structure that makes certain things quite a bit more expensive).

Tl;dr: The only constant thing is change - looking abroad helps to see possible versions of the future.