bits is bits

Being a retired IT tech, Iʻm a "bits is bits" guy. I keep seeing people rank different  streaming services against each other and I have to say, Iʻm mystified. Modern recordings are all digital masters and remastered. If two different hi-res streaming services, say Qobuz and Tidal, have the same track available, why would one sound different from the other, let alone better?

The stream is being fed over TCP/IP from the source, and I see no reason that it you were to do a cksum on the same file/track being delivered by either streaming service, that they would exactly match.  So why do people claim better sound from one streaming source over the other.  Iʻm assuming they are both full resolution sources, not mp3.