When I first came to Japan, I spent a lot of time getting to know the Japanese culture, including the Japanese entertainment industry. I had my regular Japanese variety TV show that I watched every week, and read some Japanese comics (although I couldn't really read much Japanese at the time).
I also tried my very best to start liking Japanese music. One good reason to learn some pop-music classics from Japan is so that you can have fun singing with your Japanese friends in the mandatory karaoke after-parties on tired Sunday mornings, and I know from experience that singing too many songs in English can ruin the karaoke-room vibe (protip: learn one or two Japanese songs, and you will earn instant friend-points with your Japanese companions). I rented CD's and copied them over to my mp3 player (yes, for some reason renting CD's is still a thing here...) and listened to everything from soft-rock and Japanese idol groups to chipmunk-style techno groups (see Perfume). However, as a person who enjoys rock and heavy metal music, I soon came to a realization about Japanese pop music:
It all SUCKS.
But all is not lost. Japanese music does not suck, good music is just not popular in the country in where it is made. A Japanese friend of mine pointed out that this may be due to the fact that karaoke is so big here, so all the songs pretty much have to be singable with guitar solos and instrumentals kept at a minimum. Also, marketing is alpha-omega for the industry, and the massive advertising companies are just too powerful for independent artists to shine through. So I did some research, and I found tons of high quality music by highly talented musicians. The Japanese audience doesn't appreciate talented musicians, but that doesn't stop the talented people from flourishing here.
As an example, I want to introduce Ningen-Isu (人間椅子). The name is Japanese meaning Human Chair, based on a short story of the same name. They are a metal band (although they are often touching upon other genres), fusing western hard-rock culture with Japanese elements such as Noh-theater and ancient Japanese poetry. In interviews they have named classic bands such as Black Sabbath and King Crimson as their inspiration. The band has been around since the late 80's, and are still releasing albums today and have quite a cult following here. Their stage show includes dressing up in the Japanese traditional attire Kimono, and the bass player dressing up as a Japanese Buddhist monk. Recommended listen!
In short, give Japanese music a chance!