I will just say that while I agree completely with what you are saying, RG6 cables are almost the standard of all standards when it comes to meeting the frequency support specifications that cable providers have. It's always one of the first questions I hear if I am having cable/internet issues in my home, which have never been my fault. But, they ask every single time, and they sometimes replace my connections with their own just to be sure of things.
Most recently though, I ran into an installation where they were using HDSDI cable instead of RG6 coaxial cable. It was a bit thinner, and more akin to RG59 cable. Thin and lightweight, but being used for the DirecTV receivers in the equipment rack and at other locations. I believe the runs were really long.
What I don't know, and couldn't tell you, is if a cable like a mini RG59 cable would be enough to carry a digital signal from the wall to your cable box or to your modem.
Mini coax cable is all I use for audio and when I was using component video, it is what I used. So, not that I am saying to buy this, but this is similar to what I used everywhere in my home system, at runs up to 100 feet, and carried 1080i video without issue along with digital audio and/or analog audio...
Belden's 4855R Mini RG59 cable is a 12 GHz, 4K UHD precision video coaxial cable. 12G-SDI coaxial cable maximizes 4K signal transmission distance on a single coax, minimizing weight and space compared to dual- or quad-link configurations. Single link runs of Belden 4855R are capable of driving...
customcableconnection.com
I might reach out to Blue Jeans cable and see if they can make you a mini cable to test with. Heck, if I have time, I may be willing to give it a try tonight in my home as I do have several leftover leads of mini hires cable laying around that I could throw some F connector to BNC adapters onto and see if they work.
Blue Jeans uses Belden 1855A and 4855R for their mini RG59, and they may have a LOT more insight than what I can offer, I will only be able to tell you if what I try works or doesn't work.
Worth adding that a 6' BNC to BNC cable from Blue Jeans is less than $25 and you will still need BNC to F connector converters for it.
PM me to see if I tried it out on my Verizon boxes or not if I forget to return to this thread.