It's Japanese Power Rangers. It's guys in leather/plastic beating up other guys in rubber costumes. This is what they primarily are. Star Trek is not classified as a war drama, and Batman Begins is not classified as a romance.
Now, if we have a Kamen Rider show without Kamen Riders/Kaijin/silly toys then we'd have a drama, but that's not Kamen Rider.
That's my opinion, anyway.