Explain.
RSE's gym leader theme not fails to properly set the mood of an important battle, but also fails as a composition itself. RSE's soundtrack is rather poor, as a whole.
This has nothing to do with nostalgia, since I like 4th gen's tracks.
This. Plus, every battle theme sounds the same to me. Well, except for the Regis and the Weather Trio. Otherwise, they're all the same. It's boring.
Also, third gen chose awful sound samples. And the GBA is capable of far better. See Golden Sun for example.
Weather Trio battle is a decent remix of a Pulseman song, so I like. :D
Original version from Pulseman.