Decided to go with the Netgear Orbi AX4200 tri-band mesh. The cost was a bit higher than I wanted, but this product appears to provide the best combination of speed, coverage and support for multiple streams. Amazon has a one-month backorder, but thankfully there are other options.

https://www.bestbuy.com/site/netgear...?skuId=6405440


I guess I will know soon if our issues resulted from the inadequacy of my dated home network equipment, or comcast overload in the neighborhood because everyone and their kids working and schooling from home...

Addendum: No issues today. The Orbi app is great - shows all the devices on the system and which stream, confirms speed test and more.