I’ve made gains with fiber internet, then CISCO boxes and fiber running to a streamer......Fiber is probably the biggest game changer (from fiber router) making these gains possible. YMMV
I have read that a few times over the years, and saw some Youtube videos where some swore by it- cheapest tweak to improve your streaming sound. So I tried it-
I got a Cisco switch with sfp output, figured out how to configure it and entered the commands to get it to work, got a 50' fibre cable and the modules, and connected them after the router and before the EtherRegen. I believe I can hear the difference, but it is very slight, and I concluded that I prefer the generic cat7 copper ethernet cable over the fibre- less "glassy" I get more of a difference in the sound by changing any other cable in my system. So for me it was a waste of $200, but you don't know until you try.
I have read numerous posts from Lumin users who claim to get the huge "game changer" benefits you subscribe to.
amplification quality with speakers are big drivers and IMHO, the amplifier is the first place for investment then speakers.
It would be nice to get some ATC actives, or a Grimm system where one doesn't have to worry about this- I admit it does appeal to me.