If they do, then it's one of the stupidest decisions I've ever seen made. When support is dropped support should be dropped, period.
I'd have to totally disagree with that stance. I have 3 x full version (off the shelf) retail copies of Windows XP Pro that I purchase many years ago, at considerable expense at the time. There is nothing in the EULA that prevents me from using it well past its end of support life and I even used one of those copies to install to a Virtual Machine about a year or so ago for a variety of purposes. If I had no way of activating it, then I would be quite peeved.
If a vendor such as Microsoft chooses to protect their software through a means such as product activation, then they are bound to honour their side of the bargain and continue to provide activation facilities for whatever time period the licensing deal states. Activation is quite different to support.
One of the big selling points and the justification of cost when purchasing retail copies of Windows XP back in the day was that it could be installed and activated as many times you wanted, to as many different computers as you wanted, so long as it was only installed to one machine at a time. Nothing in the Licensing Agreement that I'm aware of that says in x number of years, I will no longer be able to activate my legally owned copies of Windows XP Pro.