Aside from the facts that not all malls are dying and that there are still new malls being built, they offer exactly the benefit you stated: "lots of stores being located closely together."
I don't believe the existence of services like Yelp offsets this much if at all. People who don't mind spending the extra time to use it and then to travel around to the places they find (or even wait for shipment) are not necessarily the shoppers a mall caters to, as they're obviously not so concerned with getting what they need quickly with minimal travel.
There's also the social and entertainment aspect to consider. Many malls have food courts and restaurants and/or include movie theaters (or even theme parks, which I find hilarious, but it's there).
Malls do often exist for and serves purposes other than just providing goods in a centralized location... but that purpose itself hasn't lost its utility.
I don't believe the existence of services like Yelp offsets this much if at all. People who don't mind spending the extra time to use it and then to travel around to the places they find (or even wait for shipment) are not necessarily the shoppers a mall caters to, as they're obviously not so concerned with getting what they need quickly with minimal travel.
There's also the social and entertainment aspect to consider. Many malls have food courts and restaurants and/or include movie theaters (or even theme parks, which I find hilarious, but it's there).
Malls do often exist for and serves purposes other than just providing goods in a centralized location... but that purpose itself hasn't lost its utility.