I consider this for excellent studio monitors. Ones that won't let flaws hide. Recording engineers need that. So why do they use garbage brand X? That's another thread--we won't go there now. But ruthless in this sense doesn't mean bad--it means you are going to get the truth--like it or not. We've designed rooms like this, and there is no where to hide. Bad recording--you'll hear it. Great recording, well that's bliss.
Most ruthless are typically high-end monitors. They don't produce so much bass to muddy things and disguise flaws, What you hear is the truth of the recording. Genelec demo'd a speaker for about $20k at CES--that exposed everything. I find Talon Hawks to have similar attributes. I like ruthlessly revealing in the right context. The Von Schweikert VR-9, while full range, has adjustable bass and in the right room can also be ruthlessly revealing.
Keep in mind, those mentioned are just examples--there are many more. Nor, do I think that ruthlessly revealing is for everyone. Many speakers can convey the music, without being so revealing and may be more enjoyable for many listeners. I own multiple systems. None are ruthlessly revealing, though some components may be.