I have heard recommendations against a mesh network for audio, as if the connection switches from one node to another, there could be dropouts. I have no experience with that myself, but it seems plausible. So maybe a WiFi extender would be better. Best, of course, is Ethernet directly to the streamer if possible. That avoids all vagaries of WiFi.
Like @designsfx , I’ve found find the router has a big influence, and some have worked much better than others. Currently, I’m using an ASUS RT-AX86U, not the most expensive, but an outstanding router in reliability, stability, and signal strength. It’s in the basement, and we get good coverage even on the 2nd floor.
Using the RT-AX86U, I’ve run my Auralic Aries G1 on WiFi for a few days, and the connection was rock-solid and not distinguishable from Ethernet. Your setup and results may vary.