So, we should refrain from using lowercase m for this.
Except that mm is already used by a number of industries and people to mean million.
What you did was quote from the first result of a google search without attribution and then pretend the quote means the opposite of what was written. See: https://corporatefinanceinstitute.com/resources/knowledge/ot...
Your quote left out the first part, which is italicized in the full quote below:
In finance and accounting, MM (or lowercase “mm”) denotes that the units of figures presented are in millions. The Latin numeral M denotes thousands. Thus, MM is the same as writing “M multiplied by M,” which is equal to “1,000 times 1,000”, which equals 1,000,000 (one million).
“People don’t understand”, none of those were at all plausible even without the context of scanning the entire IPv4 address space.