Selecting a grab-bag of "THX" gear and hoping it all sounds great together as a ’team’ is an interesting approach but one I’d deem aimed more at mid-fi, and folks who don’t have the time or inclination to audition (or don’t trust their ears if they do).
I think that is a fair assessment, exactly the market that needs something like that to guide them +1.
The THX rating seems to also have a high end market as well, Perlisten, KEF, Meridian, Parasound, and Benchmark. KEF’s US demo room at their NJ HQ is THX Dominus certified and they wear that like a badge of honor. Perlisten partnered with Storm Audio and Dirac at CES and bragged about their THX Dominus creds, this room is pretty high end:
Look how Benchmark positions their THX amp in the high end:
Pair the DAC3 (DAC-preamplifier) with the AHB2 (power amplifier) to create the ultimate high-resolution music system. These matched Benchmark components are designed to reproduce music without imparting audible noise, distortion, or coloration.
https://benchmarkmedia.com/collections/amp