Where I live, there are...maybe around a dozen proper stereotypical malls within an hour drive. Of those, the two malls I literally grew up in have had very different trajectories.
The one next to my highschool is a veritable empty shell. I think it sits at 40% occupancy, with entire wings boarded up, lights turned off and otherwise abandoned. When I was in High School it was the city center, so bustling and full of people it was often hard to walk in a straight line. I'd leave school and go to the mall instead of taking the bus home, mill around in the arcade for a bit, eat some cheap Chinese food in the food court, bum around in Radio Shack or the electronics section at JC Penny or just hang around with friends mallrats style. It seemed like it would stay this way forever.
But some key demographic shifts happened in the 2000s and the entire city changed, leaving the mall a grotesque enlarged gangrenous tumor hanging off of the attached Walmart. Strangely, the arcade that was there, then closed, is back open again and one of the few signs of life in the entire place.
I've thought a lot about what happened, and the basic conclusion is that it had to do with the housing boom and bust. In the 2000s as the housing market was exploding, people who had lived in this older city suddenly found out their houses had doubled in value. They sold them off and turned the equity into a down payment on a new house in new suburbs. Those new suburbs came complete with new malls (the two new malls near the new suburb I live in are pretty jam packed all the time) and everybody left.
So who bought those old houses? The people who were working on building the new suburbs. In this case largely immigrant workers from Hispanic countries. They needed the cheapest possible housing, and these older areas, though now much more expensive, were still lower cost than the new suburbs.
Because of the higher housing costs and the lower pay these new immigrants had, expensive mall shopping just wasn't on their regular agenda. Better bargains were the draw and Walmart boomed, outgrew their original store and struck an agreement with the mall for cheap property and rent if they could become the new anchor at the mall. If you drive a circle around the mall these days, the parking lot outside of the Walmart is packed to the gills, there are maybe 2 dozen cars in any other lot at the mall combined. A walk through the mall tells the same story, Walmart is buzzing with activity, but right outside the doors, nobody goes anywhere else.
To give you an idea what a huge shift this is and that I'm not imagining it, when I graduated, my highschool was something like 85% White, and 3% Hispanic. In 2012 it was less than 30% white, and 42% Hispanic. For comparison, the demographics of the entire region are 55.41% White and 16.3% Hispanic.
The other mall, in another nearby town, is doing well. It's a larger mall, and the demographics of the area didn't really change all that much. It's not quite as busy as it used to be, the anchor stores seem to be the most empty, but it seems to be getting along fine.
Now in the 2000s, two new malls sprung up in the newly built suburbs. One, a traditional all under one roof enclosed 1.4 million sq ft mall. It's new and pleasant and does pretty well. It's not packed at all times, but business is obviously doing well enough there. The other is an open air discount outlet mall and it's packed, shoulder to shoulder, at all times. I bet if I were to go there right now I'd have trouble finding parking. It's booming, and there's talk of them expanding the property to a sister mall across the main town thoroughfare with a connecting pedestrian tunnel.
There's also a pair of high-end luxury malls in another nearby town that have been through all of this pretty much without hiccup. A time traveler from 1998 to today wouldn't notice much difference except for the fashion.
So yes, I think some malls are dead or dying. That much is clear. But I think the reasons for it are more than just Amazon. There's still lots of services I get from my local malls. I don't go every week, but the 3 or 4 times I do go I inevitably walk out with a few hundred dollars worth of clothes and other goods. And looking at the other people there, the demographics span from young to old, I don't think Amazon has quite replaced the kind of buying where you have to go see the product.
Some stores have caught on to this, and have a seamless exchange program from their online stores. They know that you'll end up buying something you don't like or can't fit into, so they let you bring it back to their physical store, because that's less hassle than shipping it back. They'll even time online sales to preceed in-store sales a bit, so when you come to the store to return the ill-fitting item, why don't you browse the 50% of sale they're offering right now?
edit
Thinking about this more, I think a similar effect can be seen in the midwest. As agriculture labor shifted to much cheaper migrant workers and automation, the people who used to live in these places year round either became less affluent, or moved away. Either way the local malls had a smaller pool of eligible customers and they die off.