Too low is just a fad gone too far. One guy lowers his car a bit and it looks really cool. Next guy figures that lower is better. Before you know it, everybody wants their frame in the grass, but can't DRIVE their cars anymore. Some guys spend thousands on lowering their car before they even spend on engine/drivetrain. You can say the same about any fad. You got 19" rims, well I got 22" rims, next guy has 24". Get carried away with it and the fad isn't cool any more, it becomes a cartoon. The next thing you know, Rat Rods become popular. Oops, that already happened.
Those are hover boards, they stay with the truck. I have a friend with a '40 GM that is pretty low and he is forever scraping the chin, but it doesn't seem to both him. It mostly happened under the bottom where it doesn't show and he has been driving the truck since the '90s.
I have an 'off topic' car which has about 5 inches clearance on the front axle unloaded. this is the lowest part of the car. I never had any trouble until one day, loaded up, I went over one of those square speed bumps that your tyres go both sides of, never been trouble before, this time stopped the car dead from 30mph. Luckily no major damage, tho the axle got a shaving and the speed bump is missing some of its front corner. Just be aware, I still wince every time I creep over a speed bump.
The insurance regulations here state that NO part of the frame, Body, or running gear can be lower than the scrub line. That is to say the rim of the wheels, when being driven on the rod.
That a serious problem if you get a flat tire, but there's lots of additional reasons to not lower too much.
A couple of decades ago I had a muscle car that I installed Hedman headers on. Those were the inexpensive brand from the old Super Shops, if you all remember them. With low profile radial tires on 14" front mags the header collectors were only about 1.5" off the ground. What a pain in the ass those headers turned out to be.
The header collectors are only 2.25'' off the ground on my new '64 El Camino...might lift the front end a bit.Luckly the former owner put QA one adjustable shocks on.