Have you looked at the basket? It’s not just a bucket. It has a perforated or mesh bottom. This is crucial. Remember that fan blowing hot air down?
The air needs to circulate under your fries, too. The holes let the hot air swirl up from below, hitting every single surface. It’s like giving your food a 360-degree super-heated massage.
If you dumped everything on a solid tray? You’d get soggy bottoms. And nobody wants a soggy bottom. Shudder.