Optimum, which bought up our previous cable company, Suddenlink (originally COX), replac ed all of their coax disdripution with Fiber several years ago. They ran new fiber links to the house, but installed RFOG (RF over glass) devices on the outside of the house, which makes the house coax system look like a cable system. They used DOCSIS modems and of course we had the same assymetric bandwidth of cable internet. When I called them a couple years ago, and said I had installed a connection to the local Fiber provideer, MetroNet, They panicked and offered me the 300 MBit "Fiber powered" cable service for $20 per month. They were bleeding customers. I cancelled my Metronet and went with the $20 deal for a year, even though I didn't like the old cable technology.
Then T-moble Fiber struck a deal with Metronet Fiber where T-mobile would take over the marketing, billing and customer relations for residential Customers. They offered a "Founders Deal" for 2 Gigabit service, symmetric speeds, for $70 per month for new customers. That included all taxes and fees and was guaranteed for 10 years. I couldn't resist. That deal is no longer offered, but I am set for 9 more years.
Now the successaor to the old local telephone company, Brightspeed has also installed a modern Fiber system in the neighborhood, but won't be getting my business. But their Fiber technology is also superior to Optimums cable based system.
With Fiber competition, the cable companies are eventually doomed.