yall have to remember, there was a time you couldn't hook up your own landline telephone without it being one manufactured by Ma Bell herself (western electric) and rented out through an installment plan on your bill.

Culturally the phone company (and the descendant cellular operators) were very much of this philosophical outlook.

This page goes into particulars about the historically closed nature of the phone system and the cases that led to the eventual opening of bring your own equipment (Hush-a-phone, Carterfone etc):

https://en.wikipedia.org/wiki/Customer-premises_equipment