Allegedly, on or about 23 July 2016, Chris Murphy sent:
Thing is, I don't see this same behavior on macOS with the same hardware and environment: I don't see the constant disconnects/reconnects, and I don't ever have BT problems.
Looking at a couple of WiFi/bluetooth de-snaggling pages, I was (a) surprised to learn that the two were in the same RF neighbourhood, that seems like bad planning, and (b) see that either technology *can* use some automation to avoid congested channels. Perhaps your Mac *is* discovering and avoiding problem frequencies with the bluetooth.
The various other solutions offered won't be do-able by everyone.
You can't always change the position of wireless and bluetooth devices, since they're fixed inside the chassis of things, unless you're using a USB dongle. But moving the position of everything to change a reception pattern may be possible, and you might only have to move something an inch to move it out of a dead zone, or out of somewhere that received interference.
Changing USB cables around may help, some are poorly shielded and radiate interference.
And if you're prone to external interference (microwave ovens, video transmitters, cordless phones), you *may* not be able to do anything about them, certainly not if they're not yours. Video transmitters often have a frequency selector switch, I know I have one with the opposite problem (it's disrupted badly by WiFi). And maybe moving a cordless phone base station could change things.