Not quite a fair comparison - different display types. Having said that, I know what you're trying to say. The Nexus 5's screen is a big let down, especially coming from the HTC One, which produces more accurate and vibrant colors. The N5 isn't perfect - the speakers suck, the camera is inconsistent, and the build quality is flimsy. But for $349 off-contract, I am willing to acknowledge they do have to cut corners to keep price down, so it's not all that bad.
Just today I switched back to my One as a daily driver, and boy did I miss it. I rooted it, installed a new ROM, and I missed the excellent display, stereo speakers, much better camera, and excellent build quality. I wish Google offered two Nexus phones - one low end and one high end. I guess the GPE versions of the One/GS4 (+ Moto X) are the closest thing.