You couldn't do that as well with different stores simply because malls have different demographics (meaning any conclusions could be noise) and the costs of shuffling where things are located is high so you can't just test 50 different setups and see what works.
Xerox is a more apt example of the 'missed opportunity' narrative.
The big old-line brick & mortar chains just didn't think it worthwhile to build this sort of granularity into their systems, and are paying the price for it. I suspect that many executives who grew up in the 50s-70s think in terms of "Is this change good or bad?" vs. "Why is this change good or bad?" (Note that brick & mortar retailers who have embraced extensive data operations - notably Walmart, Target, and Safeway - are doing great. It's the Sears & JC Penneys of this world that are failing.)
I wouldn't be so certain of others ignorance. Retail stores have long done studies and applied consultants to problems on layout, music, pricing, etc.
What makes this hard, is that for all of these companies, machine learning models are essentially used in place of heuristics of varying degrees of complexity. The models are being used to incrementally improve heuristics that in some cases are tuned quite well. Couple that with the issue that a machine learning model is only one piece of an actual product improvement for these websites/companies (ie: now you have a prediction, what are you gonna do with it to effect the product?), and all of the sudden you have actual incremental improvements completely misaligned with moonshot expectations.
We've had plenty of rankers and recommenders for decades, the current wave of deep learning variants are improvements, but they're incremental from a high level. If your business wasn't successful/is failing using simple heuristics (sears, jcp, etc), a machine learning model isn't going to magically correct that.
Does it actually? Specifically, what has AI done for Uber?
A secondary issue with business data is that vast majority of the features are categorical, for example: vendor id, client id, shipper id, etc. These usually get hot-one encoded, and you end up with hundreds of features where there's no meaningful distance metric. Random Forest and XGB are about the only that produce somewhat rational models, but in reality, they are good because they approximate reverse engineering of business process.
And lastly, the hype far outweighs the possibilities, at least until the business are ready to re-engineer the processes, if it's not too late.