You just linked to a wiki article that says country music has been around since the 1920s. That same site says a generation is 20-30 years, so 3 to 5 generations of country music.
For example, Hank Williams played country in the 40s for one generation. His son, Hank Williams Jr. played country music in the 70s for a different generation. His grandson, Hank Williams III, played country for yet another generation in the 90s. His great grandson, Coleman Williams (aka IV) plays country for today’s generation.