This is far from underrated.
Improved research needed here, the #2 most popular music artist in US history is a Country act, plus 2 others in the top 10 regularly crossed over into Country.
One might even say The Beatles did at least a couple of Country songs, including "Act Naturally" [a cover though], and "Rocky Raccoon".
As a country fan living in Hong Kong, I'll say this: The genre seems to be very popular in the USA, but country hasn't had as much global popularity unlike many other American and western music genres like Hip-Hop/R&B and electronic music. But things like increasing globalization and music streaming, more liberalism in country music, and the Country 2 Country festivals seem to be changing that! I do hear mainstream country played in Asia sometimes!
What the heck!? Metal is awesome! So are all types of Metal.
4 Heavy Metal Heavy Metal music is a sub-genre of rock music that originated in the late 1960s-70s, featuring more distorted and heavier instrumental work and darker lyrical themes. Heavy Metal broke into mainstream success with bands such as Black Sabbath, Iron Maiden and Metallica. ...read more.
5 Hard Rock Hard Rock is a subgenre of rock music known for having heavier guitar riffs/solos. It originated around 1964-1965 with various Garage Rock bands.
Jazz is not really popular to most people. I'm not one to start a stereotype but I think jazz is only enjoyable to most old people.
11 Rock Rock music is a music genre that was created in the 1940s. The genre got popular during the 60s, 70s and 80s. Rock bands generally consists of a guitar player, a drummer, bass player and singer. There are a lot of rock subgenres.
Never heard of it, so it must be a good contender.