> The whole "security" thing is a sideshow; the real goal here with "Secure" Boot is to make it harder to install unlicensed copies of Windows.

How does that make sense? The Lenovo laptop in question, like most non-Apple PCs sold in the West, came with a licensed copy of some version of Windows; and Microsoft's strategy lately has been to offer (almost coerce) free OS upgrades, apparently valuing users being up-to-date over the revenue it could gain from the meager fraction of users who'd pay for upgrades. So there's little reason for users to ever install pirated copies of Windows on such devices, or for Microsoft to care if they do (in order to downgrade or whatever).

In China and elsewhere the situation is different, but since the manufacturers are "in on" the piracy, there is no reason they'd enable any firmware features that could hinder users from installing pirated Windows; and even if a future version of Windows requires Secure Boot, that would just be patched out along with the activation checks. (That is, if China ever gets off Windows XP!)