It was because of anti-monopoly legislation, https://www.investopedia.com/ask/answers/09/att-breakup-spinoff.asp https://www.investopedia.com/ask/answers/09/att

It was because of anti-monopoly legislation, https://www.investopedia.com/ask/answers/09/att-breakup-spinoff.asp https://www.investopedia.com/ask/answers/09/att-breakup-spin... ; i.e. breaking up 'Ma Bell' into the baby bells, and the current oligopoly we have instead in the modern day. An older picture showing how they were broken up and then re-merged: https://www.reddit.com/r/Futurelings/comments/r24ed0/diagram_of_how_the_baby_bell_breakup_and/#lightbox https://www.reddit.com/r/Futurelings/comments/r24ed0/diagram... or https://legalclarity.org/what-happened-to-the-baby-bells-after-atts-breakup/ https://legalclarity.org/what-happened-to-the-baby-bells-aft...