A family of Microsoft word processing software products for creating web, email, and print documents.
The reply in that article simply is wrong. That Math AutoCorrect Preference in Word does not affect any other program.
In Mac PowerPoint you need to select Equation on the Insert tab in order to get the result you're looking for. Those entries only work in math regions [i.e., equation content controls].
Also, an additional key [such as <spacebar>] after the shortcut needs to be pressed in order for the conversion to occur.