Why do many discussions about sonic performance disintegrate into technical discusions?

Philosophy exists because it says so.

So there!

Besides it's a bit of a joke, in that music is about feeding the inner barking monkey - the ego and the body's emotional core.

Good luck in trying to be objective with that. Logical? Sure. No problemo.

But fundamentally Objective? No point.....

When we look at audio designers, they'll help you (or at least show some potentials) with your quandary in these areas. They design objectively, or creatively in a objective framework. The vast majority of them will then say they listen to the gear, after it is done or prototyped. If it does not move them emotionally..after all that objective work...then the wiser ones will scrap the new work or alter it until it does move them emotionally.

As it don't mean a thing if it ain't got that swing...

The swing can be objectively identified, IMO and IME, but it's a fairly tough nut to crack.

OP, as you have suggested at the end of the day, first is sonic performance, being the most important. Stability and functionality is second but perhaps can be equal first. How it is made is absolutely third to sonic performance and although can be sometimes interesting.

As regards technology being based on data, that is actually generally not true inasmuch as the only data is about technical performance when what is needed is data about the listener's reactions.  As well, technical innovations are often confounded by other changes in a product such that even if everyone agrees that a new product is better you can't actually say why. 

Audio is about technology but the discussions of the technical advances almost always have less merit than the authors believe because they lack evidence that the supposed technical advantage of, say a new amplifier circuit, is what really makes the new amp, which employs it, actually sound better. Almost always with new products, the new technological innovation is confounded with other changes in the product. For example higher grade components, such as capacitors, resisters, volume controls, transformers. Or in a topic near and dear to my heart, additional mechanical damping. What is usually missing is a controlled comparison where two amps are compared with only one variable changing, such as the circuit.

So talking technology generally creates a false impression of scientific exactitude. And to be clear, I am not just talking about amplifiers.

I am with Geoffkait. These threads sound like something Woody Allen wrote. The male male egos here can't even agree on the definition of technical.