The proof is in the pudding. But don't take my word for it. Do your own research. Links are in the description.
A lot of pretty misguided stuff there. I didn't see where he did any UV exposure testing, which to me is one of the most important parameters of lines used outdoors. I used my 3600w UV lamp array to expose LMR cables (in my case, LMR240, 400 and 600 only -- there are others) for 1000 hours of accelerated life testing and saw no degradation in appearance or electrical tests including hipot (600V for 240, 3 kV for 400 and 600) and pressurized moisture intrusion; most RG8X and other commercial (non-mil) cables fail this miserably. Haven't tried this with the M&P cable but would like to. If it stands up as well, that would be very good -- but it's something that really should be tested. And it's not difficult to do if you have twelve 300W UV lamps and don't mind the small hit on the electric bill. This is just one of the myriad tests Western Electric used to do on anything used outdoors, I learned it from them. Their tests went on for months, sometimes years. I don't have months or years, but after doing this on some "hobbyist" coaxial cables a few years ago it was an eye-opener.
ABR Industries ABR-400UF. I have used their coax going on 6 years now with zero problems. American made and 100% quality coax!
