People cannot be trusted to use "megabyte" as a word. Too many people use it to refer to 1024 and not to the correct SI meaning of "mega."

This can be solved by introducing "kidi," "medi," "gidi," and so forth meaning "kilo (decimal)," "mega (decimal)" and so forth. These new prefixes are completely synonymous with kilo, mega, giga, and so forth, but have the advantage that sloppy developers from the 80s haven't misused them yet.