Yet another wifi problem

I've got a fair amount of Sonos gear, but I'm starting to get fed up with the poor wifi in their speakers. The stuff in my TV room - Arc, Sub min, two rear Ones - works fine. I have a Sonos amp in my office, and I rarely have problems with that. But in my bedroom, there have been problems for a long time.

Previously, I had a pair of Ones, and the right speaker signal dropped out often. Sonos suggested changing the wifi channel, and I did that, and it was improved.

I recently update to a pair of Era 100s, and it's even worse. Almost every time I listen, one of the speakers goes offline and reboots. Sonos support says that this is because it's searching for a good wifi connection, but I have a Netgear Orbi wifi 6 mesh system, and in that room, I get several hundred Mb/s in speed tests. And this is with an access point less than 20 feet from the speakers.

No other wifi device I own - and I have quite a few - has problems with this. The wifi radios on the Sonos gear must be underpowered, and the technician said as much. 

I may end up selling the Era 100s and buying a pair of HomePods. They're more expensive, but they never drop out (I have a pair in another room).

Any suggestions for those who may have resolved this issue, which seems way too common? 

Before anyone suggests using SonosNet, the Era speakers don’t support it.