Some years ago Comcast replaced the coax with digital fiber in our neighborhood. However, the line into a house remained coax.
They did introduce -- at a premium price -- "digital" service which required renting a converter box from them. That eliminated the "cable ready" function of TVs and VCRs which reduced service.
They required certain services such as premium HBO to go digital meaning you had to rent the box in addition to the premium price. They also eliminated free FM radio.
I suspect one motivation for their work was better security. Under the old system, it was easy to hijack a local box to get premium channels, harder with digital.
[TELECOM Digest Editor's Note: Several years ago, when I first got 'cable TV' here in Independence, I hooked my Bose radio's antenna connector to the cable line so I could _clearly_ get some FM stations 80-100 miles east of me, in Pittsburg, KS and Joplin, MO at no extra charge from cableco, because I know that cableco carries two or three (NPR-type) FM stations on a 'free-ride' basis.Anyway, one day the lady at our local office of CableOne told me if I wanted to purchase 'digital cable' I could since there is a large number of radio stations on it, but I told her I did not need to pay for FM radio since KOSU has a local repeater station (KOSN 107.5) a few miles away -- it now comes in like gangbusters, like a local, even on my small bedroom radio and that is about the only station to which I listen, plus the Joplin, MO/Pittsburg, KS station (89.9) now and then, and its on the regular cable free of charge. She sort of frowned and said "oh, you knew about that ..." and I told her I did. Plus, the literally jillions of radio stations which simulcast on the internet.
I put a sort-of quasi-like 'radio player' on a web page of mine with a choice of about a dozen stations from around the world. You can see it and listen to it -- although you may not like my audio choices -- (a few 'on demand' and a few live streams) at