I may be completely off-base since Microsoft surely has some numbers we don’t that justify their choice of licensing model, but from my perspective, and from a few real experiences helping family and friends, people figure their PCs were at the end of their life and needed an entire replacement. Installing the free Windows 10 upgrade changes their mind - now they think their computer is perfectly up to date, at least for a few more years. These are machines with specs that look like Core 2 Duo or 1st gen Core i3, 250 GB spinning rust drive, 4 GB RAM. Those specs are especially prolific in decommissioned office PCs sent to recyclers who give them a fresh 7 or 10 license. They’re cheap, plentiful, and come with warranty, so plenty of people go for them.

Another thing to consider is volume licenses weren’t able to take up the offer - the company had to pay for their Windows 10 upgrade. Enterprise licensing is the Microsoft money maker.

That should be plenty for the basic 'grandpa wants the internet and Word' use cases, though. If it's not, I blame Microsoft.

Not using Windows, but I have some machines with similar specs and they are quite useful even for browsing many if not most websites. But, you must have NoScript and ad blocking.

So to be fair to Microsoft, at least some, if not all of the blame must go to web developers.

Fair point, there probably was an element of trying to prolong machines' lives longer than usaul going on, all right.