Mind-boggling that any retailer would not have the capability to at least run the checkout stations offline.

You can, but it's all about risk mitigation. Most processors have some form of store and forward (and it can have limitations like only X number of transactions). Some even have controls to limit the amount you can store-and-forward (for instance, only charges under $50). But ultimately, it's still risk mitigation. You can store-and-forward, but you're trusting that the card/account has the funds. If it doesn't, you loose and ain't shit you can do about it. If you can't tolerate any risk, you don't turn on store and forward systems and then you can't process cards offline.

Its not the we are not capable. Its, is the business willing to assume the risk?

I knew an old guy in the '00s who specialized in cobal/fortran for working on tiller software. Guess he retired and they couldn't maintain it

Anyone remember Bob's number?? Bob?! Oh the humanity! We're all gonna be canned!

Most retailers trust their cashiers a bit less than they trust the customers. They'd rather shut down during a power/Internet failure than give any autonomy to the worker drones.