It is harder to put any specific genre in a box that much most of the time. Some artists that often were classified as country really weren't that much. Anne Murray, for example. She did do a remake of a George Jones classic, but other than that her music was defintely much more pop than country. I once read an interview with her in which she reasoned that they probably classified her as country because they didn't know how to classify her.

It was, IMO, in the 1970's when country started to become much more pop-oriented. A few country stars of the time even did disco-fueled songs when that short-lived genre was in its heyday in the late 1970's. Fast forward to today, and it's very hard to, say, compare Kenny Chesney with George Jones or Carrie Underwood to Loretta Lynn. Sometimes I regret that we have gone too far away from traditional country, but we had country-pop hybrids before. Think "White Sport Coat" by Marty Robbins or the rockabilly acts such as Elvis and the Everly Brothers.