This one will probably invite some withering mockery, but I will ask....
I only stream, and my streamer (Bryston BDP) is fed with an ethernet cable that runs back to my router. Literally back to my router; there are enough output jacks on the router that I have a long run to the streamer and no ethernet switch in the chain (or the house system for that matter). (There is an Eno filter right before the streamer).
I happen to OWN a nice LHY ethernet switch. I am assuming that there is no reason to use it in this configuration, that is, assuming there are noisier switches, and less noisy switches, there is still no net benefit of adding any switch to this chain. But maybe, just maybe, in the metaphysics of electrons that I do not understand, there is some reason why a nice switch prior to the streamer accomplishes something (in theory...I get that I can A/B test and try to fool myself whether I can hear a difference). For the first person with a correct answer, I will mail a nice $600 switch to the address you specify! (JK)