I am also a retired IT guy with 35 years of experience. Without getting deep into the never ending arguement as to the "bits is bits", the big differences in the high to low end streamers are usually include:
- general quality of components, including power supplies and shielding
- how they handle the inherent jitter in the digital side, and the quality of the digital clocking circuit
- how noise (electrical circuit and EMI/RF) is minimized or filtered out
- amount and speed of buffering of the streaming data is available
- and probably the most important piece, is how well the digital "file" data is converted into the 'next' stage signal... such as analog if using the internal DAC, into an optical signal, SPIDIF, or HDMI.
And as @gkelly mentioned... typical computers are among the among the worst at just about all the above issues.
As for Qobuz sounding better than Tidal, I agree. Not bringing hi-rez files into the discussion, I think a lot of it has to do with possibly different masters (or remasters) supplied from the original source(s), as well as differences in encoding software used to create the streaming file. While I've never seen any info from either Qobuz or Tidal on what the format(s) they get or use for the "masters", I don't think those masters are what is actually streamed. Most likely they are ripped or converted (or down sampled from hi-rez, DSD, etc.) into a FLAC, AIFF, etc. file. So different software, configurations, equalization settings, etc. would create differences...
... Just my 10 cents (adjusted for tariffs and inflation... lol)
Jeff