Why are all the lab radiants so elogonated?

[Scooba116]

I thought perhaps tastes had changed, but the mined radiants are mostly still more stout. I've having the hardest time finding a more traditionally shaped lab radiant, and the ones that are stout are double or triple the price of the others. What gives?

ETA: I'm looking in the 3.5-5 ct range if that matters.