For Sonos’ purposes, the extra speed makes no difference. For other purposes, YMMV. 

what is YMMV?

Dammit. Called out on my own pet peeve. I should have known :)

It’s a common phrase used in advertising in the US when talking about efficiency of cars. Frequently abbreviated in text, it really stands for “ Your Mileage May Vary”, which means your experience may be different than others. 

Apologies. 

no worries. I’m in Australia.

My experience has been that the WiFi6 access points are generally more capable than WiFi5 access points. Part of this improvement is probably due to faster internal processors and part is due to WiFi6’s improved capabilities. Full benefit of WiFi6 is realized when all clients support WiFi6.

Adding mesh points can be a mixed bag. Yes, a client might have a better connection to the local mesh point, but the mesh point must then communicate back to central -- possibly incurring delays. If the mesh point is wired back to central, this delay should be minimal, but a wireless link could encounter reduced signal strength and interference -- exactly the same issues that the original client connection might have experienced. Placement of wireless mesh points might be counterintuitive. The first thought is to place the wireless mesh point near the client, however, this is probably counterproductive because the mesh’s wireless connection is not much better than the direct connection of that client to the former central (the old ISP access point). A better plan would be to place the wireless mesh point about midway between central and the client area. This will give the mesh point the advantage of a better connection to central and this advantage can be passed through to its clients.

Clients might not be taking full advantage of the mesh. Consider the situation when client ‘A’ is connecting with access point ‘B’, then the client phone/pad is moved far from ‘B’, but near access point ‘C’. If ‘A’ is stubbornly holding its connection to ‘B’, connectivity will suffer. Momentarily switching the phone/pad to airplane mode will allow it to discover the better connection to ‘C’. Some premium mesh systems will figure this out on their own and ‘B’ will dump ‘A’ and transfer it to ‘C’. SONOS WiFi connected players don’t always react well to this transfer. If one or more SONOS players are wired to the network, they’ll form a private mesh network (SonosNet) that is very robust and designed for playing music. ROAM and MOVE are always WiFi only.

Thanks. I might connect the Sonos Amp directly to the router via Ethernet. In any case, the TP link Mesh I installed is pretty good for the price but the more expensive and WiFi 6 models offer AI switch which basically does what you just mentioned. The router will send the strongest signal to the client based on where the client is at the time.

If you connect one Sonos to Ethernet all, except Move and Roam, should move off your WiFi to Sonosnet.

For me that was the best solution, only thing to watch is keeping your WiFi and Sonosnet on different channels.