Ma Bell was constantly driving technology change. Bell Labs was one of the greatest sources of innovation on the planet.
Bell Labs was great at invention, but AT&T had little incentive to deliver innovation to its rank-and-file customers. My parents had the same landline phone for 20 years, and were paying C&P Tel. $5 a month for it until the law changed allowing them to buy their own phone. And Ma Bell wasn’t necessarily the worst of the phone monopolies. I lived in Durham, NC in the early 1970s which was “served” by GTE at the time. Now, *that* was third-world phone service.