Fundamentally the use of allow_abbrev=False is now broken (it is allowing abbreviations when already explicitly told not to)

The use of a single - for all options is much older than -- and exists in my unix utilities and many programs have been written to follow this convention, these are now broken in 3.8+

"Changed in version 3.8: In previous versions, allow_abbrev also disabled grouping of short flags such as -vv to mean -v -v"

Does not accurately describe the behavior change, it is more broadly injecting abbreviations when already told not to.