This bloom effect is actually quite different from Killing Floor. Its 2D rather than 3D bloom, therefore if you walk up to a light, there is no bloom, only at a reasonable distance you can see the bloom and it actually looks nice.
(by "3D bloom" you probably mean HDR.) there's the so-called
bloom effect, which is only a post-processing effect, and affects the whole screen. it strains the eyes more as the bloom effect intensity parameters increase. there's also the so-called
high-dynamic range lighting, a lighting and post-processing technique to generate bloom around the overlit points of the screen. with appropriate HDR intensity parameters, in most cases blooming is minimal. i haven't played Killing Floor, but from the screenshots it appears that KF applies both. and as you can see, KF takes blooming to a "whole new level".
