You can have a car pretty high, and still have the crank 24" centerline. It's just a question of how deep the engine is in the frame. My '63 Falcon set up high, and was well below the 24" NHRA rule.
My Austin has the engine set so low I can just barely access the spark plugs above the frame rails, so it's well below the 24" rule.
I personally don't see an issue with some of the cars Scott posted as not gassers. But some of them are more 70's style street freaks. The blue '59 Rambler 2 dr. sdn is a neat car, and doesn't sit too high. A radius and wider tires would be neat, but a lot of gassers didn't have any different style in the day. The black Comet I think doesn't look like a street freak.
But I tend to be more lenient about gasser style builds than some. It's pretty easy to pick apart almost any modern build, but most of the time those who do it don't have any gasser at all, or have one that could also be picked apart. Afraid if I got too critical, somebody would easily turn that back on my builds too. Just my opinion.
It does seem that many are going for at least nose high, and some high all around. But that's not necessarily wrong for a certain era. Didn't see it in the late 50's, nor the late 60's. But this was also a trend in the 60's before slicks got to be much better.
Here's aa picture of Ohio George's '33 Willys around 1959:
And that same WIllys a couple years later:
Just before switching to the Mustang George had dropped the frontend significantly to get a nose down stance, and try to streamline the old Willys coupe.
A lot of other prominent gas class competitors who ran similar cars for over a decade also pushed the 24" rule at some point, but also changed once they didn't need the car's stance so high anymore. So guess it depends on which era you're copying? Some are just copying the street freak era of cars that never saw the drag strip at all, and are built more for shock and awe. And a lot of folks who don't know the history think these sky high builds are copies of gassers, and fall for the crazy high builds as reality, not the fantasy builds they are.