Even if it isn't immediately DOCSIS compatible...
Heck, just get a single packet of data over a cable from point A to point B using an open FPGA-based design... Put that on the Internet... that's the starting point...
Let it evolve from there...
Really, we need more fiber optic everywhere. It's easier to hack on, because cable modems are technically radios, and run into the usual FCC red tape. Plus, fiber is just better.
But tbh that's been my experience with most technicians accross ISPs, they're generally nice and willing to fix a problem once they're there. It's getting the office to actually send one out (like you said) that's the issue...
checked the spectrum website for compatible modems available on the market, ordered a DOCSIS 3.0 Motorola Surfboard and when the technician came in, he pulled cable across our (admittedly tiny) apartment to where I had all my networking gear mounted to the wall on 3M strips
great experience
the actual internet itself, not so much, but that has a lot more to do with the terrible nest of interconnects in older apartment buildings in New York than Spectrum's upstream network capacity
[1] https://www.spectrum.net/support/internet/compliant-modems-c...