It's not even really prescriptivist thinking… "Kilobyte" to mean both 1,000 B & 1,024 B is well-established usage, particularly dependent on context (with the context mostly being HDD manufacturers who want to inflate their drive sizes, and … the abomination that is the 1.44 MB diskette…). But a word can be dependent on context, even in prescriptivist settings.
E.g., M-W lists both, with even the 1,024 B definition being listed first. Wiktionary lists the 1,024 B definition, though it is tagged as "informal".
As a prescriptivist myself I would love if the world could standardize on kilo = 1000, kibi = 1024, but that'll likely take some time … and the introduction of the word to the wider public, who I do not think is generally aware of the binary prefixes, and some large companies deciding to use the term, which they likely won't do, since companies are apt to always trade for low-grade perpetual confusion over some short-term confusion during the switch.
Does anyone, other than HDD manufacturers who want to inflate their drive sizes, actually want a 1000-based kilobyte? What would such a unit be useful for? I suspect that a world which standardized on kibi = 1024 would be a world which abandoned the word "kilobyte" altogether.
> with the context mostly being HDD manufacturers who want to inflate their drive sizes
This is a myth. The first IBM harddrive was 5,000,000 characters in 1956 - before bytes were even common usage. Drives have always been base10, it's not a conspiracy.
Drives are base10, lines are base10, clocks are base10, pretty much everything but RAM is base10. Base2 is the exception, not the rule.