As to NAS, the two firms that spend money on R&D and software development are Synology and Qnap. That’s why you’ve heard mostly about them.
By reputation, Synology is easier to use and configure, while Qnap provides more hardware power for the money. That is somewhat overcome by Synology’s better optimizations. I have a Synology DS414 that is still going strong, 8 years later (though I've replaced the disks).
You can read more at the SmallNetBuilder Forums.
As to spending many multiples of the price for boutique audiophile products, I have seen the reviews but remain dubious. In 55 yrs of audiophilia, I’ve seen positive reviews of a lot of stuff that we laugh at today.