Donburi is the most honest argument for simplicity in a bowl

The constraint angle you're describing mirrors something I've noticed across different culinary traditions. When a format forces every element to justify itself, it creates this pressure that actually trains technique rather than just speed. A cook working within donburi's structure has to understand temperature control, seasoning balance, texture layering in ways that someone throwing together five components never needs to develop. The economics matter too, but the real insight is how limitation becomes a filter for genuine skill. That's the distinction between a place that's optimized and one that's actually thinking.