I suppose contemporary shopping goes two ways – online or the shopping as a leisure activity experience in some kind of Westfield-type mall. Unless a high street is convenient for foot traffic, people don't go there to shop unless they have no choice.
I confess I buy most stuff online. I don't see shopping as a leisure activity so I just want it over and done with. I can do that with a few clicks without leaving this seat. Choice, I think, is often a lie. Does anyone need 94 types of brake block? Or 10 types of cornflake? I doubt it. I read a study somewhere where the authors compared the actual range of a small high street convenience store and supermarket, and they wasn't that much difference in terms of type of item. It was just varieties of the same item. Advertising has done a great job of convincing us we not only need our favourite brand but we somehow have loyalty to it.
Change is normal, we're no longer a society were the housewife can pop out to the butchers, bakers etc. everyday at 11 (like my gran did, without fail). High streets can survive by providing a place to go and socialise, for the sort of shops that can't easily be replicated online, etc. And a plea to localism, give people an excuse not to get in their car and go to another grim out-of-town retail centre so they can wait around in a warehouse for a bored salesperson to tell them that no, they don't have it.
Of course, we no active planning that supports that kind of development, high streets become channels for cars and people going somewhere else, and you're left with the people who don't have choice. That means betting shops, fast food, and convenience stores with cheap booze and lottery tickets.