> As a side note, it's a shame that the Anniversary Update requires so much space.

It is a great shame. Windows 8 tended to use WIMBoot on these type of machines. That uses huge amounts of space and causes some problems for updates. https://technet.microsoft.com/en-us/library/dn594399.aspx

Windows 10 tends to use CompactOS. https://msdn.microsoft.com/windows/hardware/commercialize/ma...

So they fixed one thing, and then broke it by imposing a weirdly large drive size limit.