Because they are expensive. At least that’s the perception. It is also very exclusive brand, with extremely strict control on dealers to avoid discounting and territorial restrictions.
Having said this, the Discrete DAC is relatively affordable starting right below $10K. Once you add one of the modules, and the second power supply, you are at around $13,000. This is the DAC I have, with the ProISL ProUSB module combo and the optional second power supply, and I am extremely happy with it. If I ever had the cash to upgrade, it will certainly be the Premier. But unfortunately prices double from one model to the next. Then once you add the upgrade clocks, powerbase, then....
Anyways, if you can find something in Used market (current model that is), grab it! Truly SOTA, and definitely endgame territory for most.