I used mesh routers for awhile. It was not an Eero 6 but was recommended to me by my dealer, so it was a high gig model. It cleaned up some of the reliability issues I was having with my modem wifi as the mesh router was dedicated to audio. It sounded fine and was I felt an improvement sonically.I was quickly told to leave a switch thread because I noted I was no longer experiencing any gains from audiophile switches or stacking switches after I was forced to change my internet from a Ethernet cable to a Eero Mesh router. I had the whole expensive chain like everyone else some time back. LPS to separate Modem and Router. A custom Linear Solution switch feeding my stereo.
Recently I was forced to change. I had no ethernet cable in the new house. I was told by a audiophile to get Eero 6+ mesh routers. They are a wifi device that create a mesh of locations receiving and broadcasting wifi. Each device has 2 ethernt ports on the back. I used one behind my audio server with a short 18 inch Cat 6 jumper to my server.
Thinking about making things better I brought my Linear Solution switch out and plugged it into the Eero, then my server into it. No audible change. I then plugged a Belkin switch into the Eero and the linear solution switch into it and the server into that chain. No change.
The Eero 6+ is a gigabyte device. Maybe being completely isolated from the data utility provides a level of clean that is negating the need for specialty switches.
People with a hard wire available should look into this. I have no way to compare.
FWIW, the setup is to install a modem as usual. Turn off the router function in the modem so it is only a modem. Plug the Eero into it and use an app to configure it. Then drop additional Eero into the house and use the app to connect it to the primary one attached to the modem that is acting as the Router. It tool all of 10 minutes. And I see no issues with sonics.
Still I was not totally satisfied with the sound and so I hired someone to install an internet cable from my modem to my system downstairs in my walkout. It took a little doing but it got done. The hard wire solution sounds quite a bit better and I haven't had any reliability issues since. Basically I feel it's one of those keep it simple solutions that works.
I don't know anything about switches or the like so I can't comment on that. I suspect that the weak link in my internet is my provider supplied modem. It's worthwhile making sure you have your service provider replace your modem to their latest every so often. My experience is that they won't tell you they have something better but if you ask they will swap it out.