Not all, but many other posts contain incorrect assumptions.
The Node 2i does all the streaming directly from the source via ethernet or wifi.
Your phone only serves as a full featured remote.
No, wifi and ethernet are not equal, but high quality wifi gear and a strong signal can be good.
No conversion to and from Bluetooth.
My phone and bluetooth receiver both support Aptx....it's good but it's still Bluetooth and not even close to what a hi res source can provide.