@mitch2 Perhaps huge and amazing may be over exuberance over an initial, formerly unheard difference, sure many of us have been here.
In going back in my mind over all streaming changes since my initial foray some seven, eight years back, there were times when a change brought about this same over exuberance. Over time I can now see changes have all been incremental, however, if I were to compare my original setup to present it would be huge and amazing difference. Perhaps you need to do this comparison in order to reaquaint yourself with the efficacy of your upgrades.
For me, the higher resolving my system, the easier it is to hear the smallest changes.
Based on your description of setup, weakest link I see is the 45' ethernet from switch to gigafoil. Moving Silent Bonn close to router, replacing standard switch would seem to be good move. I'm lucky in that my internet service comes into my dedicated listening room, but at one point had this setup at far end of room, running 25' ethernet from modem to router (which is close to audio system). I then decided to setup modem close to router via 25' longer coax, so now I could use 1m ethernet from modem to router, no ethernet longer than 1.5M in entire streaming setup. So between shorter ethernet which also meant I could use better ethernet (
various generic to Supra to AQ Cinnamon, long cables, to AQ Vodka, short cables). Both shorter and better quality ethernet cables were meaningful upgrade for me.