I seem to recall similar issues for OSX users wrt wifi, and also smb/cifs support. Nothing is seamless for everyone, as it's impossible to test every system... The fact that Apple doesn't get it right on their very limited range of internal hardware is a testament to that fact.

I'm actually stunned by Apple's wifi connectivity issues.

I don't know of OS X breaking updates as acute and widespread as Windows, but the space of Apple machines to test is small and predictable, where Microsoft faces an essentially impossible testing task.

Beyond that, though, Apple laptops seem to just have shitty wifi connectivity. At a guess, it's one of the downsides of metal unibody design (along with godawful native speakers), but it seems almost universal. Things have improved, but strength, speed, and range never seem competitive with non-Apple machines at a similar price point (or half that price point).

Fortunately, I tend to lag for months usually before updating major osx versions (I don't use my personal laptop much, and at work it's farther behind still), so didn't experience the wifi issue, but did with the cifs/smb change away from samba.

I haven't had connectivity issues, other than it takes a while to switch networks... At home, my macbook has about the best connections of any of my hardware, though my Nexus 6P may be better. I've been able to reliably copy files at 200Mbps+ over wifi. Worth noting I've got fewer than a dozen devices on wifi, and neighboring signals aren't that bad where I live.

At work, it's a bit noisier.

I didn't say it was perfect, but I would be surprised if it didn't block more potential issues than it missed.

Is a 51% success rate really good enough to justify unleashing the OS upgrade right now? Why not make the upgrade opt-in, continue improving the migration wizard over the next years, and start the upgrade campaign in two or three years when it becomes both stable and more pressing to migrate people over?

It would be less of an issue if more vendors submitted drivers to Windows Update. As much as I am "happy" with my cheap TP-Link 802.11ac NIC (I use a lot of TP-Link gear in my house, my TG1600-24TS switch is great for the price too) I literally cannot reinstall Windows without having the driver disk at hand or plugging in my powerline network adapter to download the drivers from their website. A lot of these issues could be mitigated by this alone, as the first thing that the Windows installer does (if you are upgrading from a running system) is check windows update for updates to the installer and compatible device drivers.

I agree that maybe they shouldn't be so persistent on trying to get people to upgrade this early, especially if you have a NIC that isn't supported out of the box or has a driver that isn't on Windows Update (because I know the first thing I do when unboxing new hardware is throw the damned CD away, the only thing I use the DVD drive in my PC for is ripping movies).