Toole, Putzys, Linkwitz et al have established very well what predicts good listener scores and have achieved such via several different means.
Genelec, JBL, Revel, KEF, Dutch & Dutch, Kii, Neumann, and others have all produced state of the art performing units meant for various sized spaces and volume levels. All showing great frequency response, dispersion, and distortion characteristics.
They all top out cost wise under $100k.
You simply aren’t going to do better spending $800k from a sound point of view and you’ll likely do much worse because those brands have the best R&D teams in the business, vs “some guy who thinks his poo doesn’t stink and that silver plating cables makes things sparklier”
There just isn’t room to make an M2 or 8381A or 15C or Kii 3 system 10X better for the money the boutique companies are charging. This will be the case until they find some way to make sound that isn't a speaker cone with a coil attached to it. And even then it might still be the case. These systems are better than your ears have the ability to perceive from a frequency response/distortion perspective, and picking between them is largely going to depend on how they interact with your particular room rather than any specific performance metric. In a well treated room with proper room correction you'd likely struggle to distinguish them consistently in a blind test.