I think the main problem is both Amazon and Google (and all the similar ecosystems) have a vested interest in rigging the results towards personal profits.
I see this more like an open index of local online stores, curated and not using scrapers/bots to index but by stores submitting their URL and search endpoint for meta-search across all their products. Let the user sort the results by price, location, etc.
Obviously there's always going to be people trying to game the system but it would still be better than what we have now, which is us consumers needing to use Google/DDG/etc to scrape through the 99:1 noise:signal ratio of search results these days just to try fluke upon a local online store that has what we want.
(Though, of course, the team behind the alternative might be better at resisting the gaming? Google, the company, isn't magic.)