Malls were always predicated on the assumption that well-to-do suburbanites, increasing in wealth and in number due to relative prosperity in the upper subdivisions of salaried workers, would spend their disposable incomes on getting boutique, brand-signalling merchandise for themselves and their children.
This was a trend that was evidently worth commercially exploiting at a time when malls were being built, but by the 1990s the demand for brand-name goods climbed upmarket enough that a new distinction had to be drawn between a mainstream mall and an upscale mall for this strategy to remain effective. New malls were built at great cost, and they took the most desirable stores, leaving the older wave of malls struggling for enough business to pay for renovations, maintenance, debt, and ROI. This cycle repeated at least one other time, when the outdoor, disassembled 'lifestyle center' became the dominant design pattern in the mid-2000s, by which point the narrative that malls are "dying" had become widespread.
Rather, the market has segmented to a degree that the concept is only profitable at the highest end, while lower offerings are proving uncompetitive with other forces in the economy, like powerful mainstream retailers with lasting appeal (e.g. Target), low-price leaders (e.g. Walmart), reliable stores with strong curation (e.g. Costco), and the convenience of ordering online (e.g. Amazon). Then, it's worth noting that the generation that's 18-35 now spends less of their income on clothes than the generation that was 18-35 when malls were big [1], and apparel stores are about half of a typical mall's occupancy.
Compare all this to Europe and UAE. Malls are doing great there. What's different? Just about everything, from the concentration of population and the particulars of siting that draws a higher proportion of people, to the value-add of having such a variety of shops under one roof, to less competition from non-mall retailers, and brand signalling still being a desirable goal.
[1] https://news.ycombinator.com/item?id=16322720