What are you going to do with all the extra time you saved by not typing out ask me anything?
Build the wall 10 feet higher!
You have a point about typing the full name for AMA as a courtesy, but it’s a kind of common knowledge thingie among social media freaks, so . . .
To emphasize . . . I agree the abbreviation should have been explained. Journalist style is to use the full name on first reference, abbreviate thereafter (with some exceptions).