Why is "punchy" a criteria? Does it sell records? Or is it that all big selling records are punchy?
Craig's answer is illuminating, bearing in mind that musicians may (and probably do) listen in a very different way than the general populace.
As musicians, we often listen for subtleties that are lost when music is overproduced with the goal being maximum volume and impact.
Going to a nightclub where a DJ is "performing" can also be illuminating (take your -30db earplugs!!! It will stil be way too loud, ugh....).
The dance floor will be packed from start to finish and the beat goes on on on on on on on on...
It's al about the THUMP!
I am lucky to be in one of the best bands in our area and well-booked.
We are pretty "rootsy" with a wide range of genres, the lead singer knows at least 1,000 songs and is rarely stumped by requests.
Our gigs tend to be at places that draw a mixed crowd, younger, older, fans of country music, fans of more modern styles, blues, roadhouse etc.
I can chicken-pick or shred as needed and will happily just lay into the groove if that gets them up and dancing.
So we play a variety at first to see what gets them up on the dance floor.
I've often said "It's not a party until a girl shakes her ass" because that's when the dance floor will start to fill up.
We do play our share of slow country ballads for older folks to show their steps, if that's who wants to dance we'll give them a set.
In that sense we are both artists and Tip Jar Whores, it all runs together.
I have friends who play only modern "Ultra-Thump" styles and some of them make a decent living out of packing the casinos south of here.
I would prefer to slit my wrists in a tub of warm water or stick my head in the oven and turn the gas on.
In the end, they are not there for us, we are there for them. In simple terms, there are still lots of folks who want to hear a variety of music actually played credibly at a volume that does not push their brains out of their nose.
As to where this culture originated, I would venture a guess that corporate "music" entities noticed what was hitting and promoted that culture relentlessly.
Listen to some modern "country" on the radio, it has become a hybrid Hip Hop-ish format.
This too shall pass but I have no idea what comes next. I'm glad I am old, I just want to play my guitar!!!