very hard to come to any conclusion with any stats. but thinking about it a bit more...
microsoft will weigh the pros and cons of stopping xp activation. they could just void all existing licences that have never been activated, probably without any viable legal challenge. after all, the world has known xp was not going to be supported/etc. the questionmark is over continuing to reactivate old licences.
the existing commercial/Govt user base is shifting. even my monolithic employer [100k employees, only got sp3 abut a year ago] is moving to 7 this year. yeah 7 not 8 🤣.
once the commercial/Govt sectors finally drop xp, microsoft's decision on whether to kill off xp re-activation will just be down to how much flak they might get from doing so from consumers.
but new boxes have not shifted with xp [outside commercial/govt] for years. pc sales are down [though people argue over the stats]. tablets are taking over. the younger generation [who more actively game] mostly use steam and xbox live, and dosbox. They are perfectly happy to shift from what they consider to be crappy XP with its 4gb memory limit and dx9.
its not clear whether there is going to be much of a population of xp users left, and if it's just a few users running old hardware microsoft could just switch off [some fuss from consumers, but probably easily handled by cheap upgrades to 8 ie £25 a pop offers] or not [not much cost to let reactivation continue a few more years, though no commercial gain from doing so].
having said all that, the simplest solution would surely be for microsoft to issue an SP4 which takes out the need for activation. that way they can wash their hands of xp without having any activation issues, people can continue to use their unsupported software if they must. but with hardware changing and directx moving on, it won't be long before nobody [significant] cares about xp anyway.
It's annoying for those of us who like to keep old boxes running, but that's about it.