They've made a lot of smaller fixes that add up to a huge difference over time, but there's still a large number of people unhappy with movement, recoil, maps etc.
I think people like whiMp, who have all the fundamentals down and simply don't make mistakes when playing probably wouldn't shine as much in CS:GO as they did in 1.6 (which sort of applies for naSu too in my opinion) because CS:GO has peeker's advantage and doesn't reward playing what we consider "the right way" as much as CS 1.6 did.
I think so. It takes away some of the credibility. I've watched some CS:GO matches with my old friends who haven't played CS in years and never tried CS:GO, and even they've commented saying the players don't look very good because spraying seems so hard compared to how it was in CS 1.6., so it makes the players look less impressive.