I use a Tp-Link Deco M9+ mesh system, two nodes, promoted as 100+ device capable, have maybe twenty-five devices total, probably 10-15 active at any time, average streaming and no other big bandwidth demands, 400/20 broadband, a lot of band competition from a dense multi-family neighborhood.
With BlueStacks Android 7 emulator on an amply equipped PC - which should exceed the processing power of any phone or tablet, I imagine…
I can do 4-up fluidly on tinyCam Pro with its settings at Main and Bitrate set at 120 KB/s. It’ll do 6-8 at times, but never rock solid for extended periods.
With the Deco mesh system, I’ve found over time that the logic that it claims to have to automatically fine tune connections does seem to work. But it doesn’t seem to retain it through cam reboots. * Must re-tune from scratch. So I don’t do the nightly cam reboots some recommend. It’s been rock solid for months. 
The only things non-standard within the settings are that all cams are individually QOS prioritized. Each has a reserved address. And ‘beam forming’ is enabled.
Owned it for a couple of years and the three or four firmware updates seem to have improved it markedly.
* And definitely not through a router reboot.