>>And these apps which are not just ported, but built for several OSes at the same time, are winning the day. Why would anyone worry about whether Office is working right, or at all, on their other machine's OS, when LibreOffice works on all of them?
Agreed. I believe that my current PC with Windows 7 is the last Windows PC I ever will buy. This one determinedly was a Windows purchase: the next one will be a device chosen according to features, price and availability of apps. It may well have Windows- but I won't care.
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1