hear me out, Regional visibility program is going to hurt both, amazon and the sellers.

1. The sellers will not get other zones of customer because of supressed visibility and there are sellers who are selling items only available in their zones, their sales will drop to 0 or close to it and such items won't be available to the entire nation, and it's anyways available locally so people in region would prefer buying from local than going on Amazon.
2. The spend on advertisement will be a waste, you can't categorise your advertisements in regions, if you run advert, it runs across the entire country and not just 1 zone, since I have buy box availability only in one zone, high chances that people who may click on my item without featured offer will not really know how to buy it (I've surveyed over 100 customers and very few of them know how to buy using the "All buying options") customers usually just look out for buy box and call it a day if it's not there.
3. The sellers won't have orders and the buyers will not have products they need, amazon will also lose on all the juicy comission it gets, overall they'll stop trusting Amazon in the longer run and will eventually drop the idea to purchase from there.
4. Amazon is trying to fight a completely wrong battle, against quick commerce companies, there is already amazon fresh for that kind of stuff. They should try promoting that instead of turning amazon into a quick commerce company.
5. The quick commerce stuff is only beneficial for the one with prime, you have to pay extra charges for items in 2 day or 1 day delivery without prime, people will not buy a product if they see a delivery cost attached to it usually.