I don't support the blatant oversimplification that ALL speed limits are set too low because of revenue, but
...aside from using a borderline insulting scare tactic, is virtually unrelated
to the issue at hand, which is whether current speed limits are appropriate in any given location(s). I've ready plenty of research that does indicate at least some are too low, and that the fixation on speed hinders regulation of other behaviors that can be more dangerous. For example, disparity in speed is known to cause more problems than speed itself in many settings, yet you can put your 4-ways on and create a slow-moving trainwreck of near-disaster on the interstate without interference unless you get below about 50% of the maximum speed. Why do we excuse that when going 5-10 over means a ticket and insurance points? It's demonstrably more
Further, on the above video: nobody should be going 65mph in a place where there's any chance of a truck pulling out from behind a blind corner a short distance ahead, which is why we don't have 65mph limits everywhere, but there are places where it is in fact entirely
safe and responsible to go 65 or even faster... generally on wide, straight roads without blind corners or even intersections.
I say this as a hypermiler who doesn't even drive the speed limit half the time: it's not as simple as any of you want to make it. With as many miles of road in the world and as many jurisdictions as there are, some are done right and some have really fucked-up priorities. I don't advocate for higher or lower limits, I just support rational judgments in every situation.
Small towns in particular are notorious for making revenue centers of minor moving infractions that may or may not be dangerous at all, sometimes accompanied by rapid drops from highway speed to "city" speed well outside pedestrian/commercial zones. Some cities have even shortened the duration of yellow lights to increase red-light infractions, knowing that it raises collision risk.