I mean the almost the exact same thing can be said about Boston. Had 0 tower over 496ft and no building over 400 ft for nearly 20 years and then boom, built the tallest tower outside of NYC. It's easy to cast stones when you don't look at yourself.
First of all, Devon is 1.688 times taller than the next tallest, whereas the Pru was 1.512 times taller for Boston.
However, more importantly is to look at the city surrounding the towers. OKC has open space as far as the eye can see. It's a huge building surrounded by parking lots and wasteland. They had no need to go that tall. 2 more economical towers (or hell, a whole complex) would have made more sense. Outside of a few square blocks that city is probably less urban than Worcester. They don't need to build up. They need to fill in. Boston was already dense as hell and it necessitated verticality.
The Boston you showed was totally built up. On the other hand, OKC doesn't need more towers. It needs an actual city!!! The fact that you compare the 2 is frankly ludicrous. Ultra dense, filled-in Boston finally going vertical, vs stagnant OKC going huge out of vanity.
Oklahoma City by stevesheriw, on Flickr
Oklahoma City by stevesheriw, on Flickr