maybe it depends on the wifi controller/chipset/driver, a la firewire?

It might be a chipset issue I suppose, but if it is I'd have thought someone somewhere might have identified it as such as was done years ago with firewire. Ethernet nearly always seems problem-free so it's not a problem related to Windows networking in principle but wifi drivers.

Macs don't seem to have the problem, which might point to it being a chipset issue and Apple being careful not to use chips that cause problems. Firewire on Macs is also generally free of the Windows chipset/driver issues.. Or maybe it's because OS X/MacOS simply isn't Windows and does things differently. Dpc latency of any kind doesn't seem to be an issue on Macs. Which makes me wonder if at least part of the issue is how Windows handles multi-tasking in general.

I have a dedicated studio wireless network just to run controllers for my audio gear as well as a wifi router in the back of my stage rack. It has been quite some time since wifi was an issue on Windows. 

The #1 issue with Win Wi-Fi issues is the "auto discovery" feature. #2 is all of the software that autoloads and begins to use an active connection.

For the average PC user, both of the above are expected (hence defaults), but for streaming functions, they become a menace.

FWIW, I've had Atheros, Broadcom and Intel WiFi chips in my laptops, none of which gave me any issues except that I switched an Intel chip for a Broadcom once because I wanted to run a hackintosh on that laptop and OSX didn't support the Intel one.

Anyway, I know this is a relatively common issue, I just wanted to give some perspective and show that it's not a completely universal problem.