"The end of Windows XP support will not affect activation, but rather security updates and phone/online technical support." has been said many times for the last few years. I agree that this is a low quality blog post.
If you have essential software or hardware that only works with XP, you could buy a cheap wired-only router for each of your XP systems to keep them isolated from the rest of your network (which a friend's skeezy laptop might be trying to exploit without her knowledge when she brings it over to collaborate on a project).
If the activation servers do gets shut off, I hope MS will release an update to disable activation or an utility to generate the confirmation ID from the installation ID.
https://en.wikipedia.org/wiki/Betteridge%27s_law_of_headline...