Jumpin Jack Flash - Seeing as we are in the era of Thundercats, Last Star fighter, Hackers. This film is relevant.
https://www.imdb.com/title/tt0091306/
I once war dialled my small villages phone code (mid 90s). Never did hit any mainframes ….
beep boop beep beep boop - ring, ring - Hello .. hello? *CLICK
beep boop beep beep beep - ring, ring - Hello .. hello? *CLICK
Yes - I've got one, most small businesses will have one (not via pbx or internal phone systems) for faxing.
Vid related - hacking networks using a fax machine. There is a full Def con vid out there