My DIY amps are the most complicated machines I’ve ever built - much more so than the DIY turntable and tonearm. Very high parts count. They are unquestionably better than anything else I’ve tried or heard, and that most definitely includes simple amps.
The ’simplest’ amp is just a modular power supply, an op-amp driver, and an output transistor. All the complexity is hidden. The simplest discrete transistor circuits are hopelessly bad.
@wolf_garcia said it well, "Simple can be bettered by "better.""