@tk21 You got it, context is everything.
@adasdad Not going to speak for ghdprentice, but my custom build streamer has been directly compared to top tier streamers such as his Aurender, Taiko Extreme, as well as to many lower tier, and it rightly belongs in that tier as both previous owners only sold after comparing and purchasing Taiko Extreme (and this prior to JCAT LPS I power it with). The top echelon streamers pay extreme attention to noise reduction via top quality power supplies, jitter reduction via latency optimization and rendering via clocking and noise reduction of various ports. So, these are some of the theoretical reasons for improved sound quality. And then we have the listening portion, some may not consider that to be valid, but between what others report and what I've experienced with streamers, sound quality is extremely variable, at least on par with dacs. I can only say, try various steamers for yourself, assuming your system has sufficient resolving powers, the value of top tier streamers will be patently obvious.
I also have the ability to directly compare various protocols via drop in PCIe cards from Pink Faun and JCAT, top flight cards are available for network, coax, I2S, AES/EBU, USB. Presently using JCAT net XE to Sonore setup (FMC to USB), sound is simply sublime! I could stay here for the remainder of my life, never heard higher resolving, greater sense of ease with digital. Had to greatly upgrade my vinyl setup to keep up. Perhaps I'll compare other protocols over time, simply not motivated at the moment.
I'd only say believe those with top tier streamers, they are indeed hearing what they claim to be hearing, they are not delusional! I don't care about the damn theoreticals, audio is for our listening pleasure, not meant for some listening bot or textbook.