To give the devil (M$) his due, if you show the properties of a HD,
WinDuhs will display the space (used, free, and capacity) in bytes
and in (software) GBs. That dual display does, at least, make it
obvious how much space is "lost" due to M$'s spacey arithmetic.
My first choice would be for M$ to conform to SI standards for HD size
prefixes, as HD vendors do. But M$ will likely do what they want, and
the confusion will likely continue. <Sigh>