Correct me if I'm wrong, but my feeling is this all started with the GPUs and the fact that unlike on a CPU, you can't really step by step debug the process by which a pixel acquires its final value (and there are millions of them). The best you can do is reason about it and tweak some colors in the shader to see how the changes reflect on screen. It's still quite manageable though, since the steps involved are usually not that overwhelmingly many or complex.

But I guess it all went downhill from there with the advent of AI since the magnitude of data and the steps involved there make traditional/step by step debugging impractical. Yet somehow people still seem to 'wing it' until it works.