On the one hand, there are certain basics of vocal function that are true no matter what style of music is being sung:
It is essential to be able to pace the breath with support from the body so that there is not too much air pushing against the voice or mixed into the tone.
The vocal cords need to come together efficiently to make the pitch.
The resonators have to be accessed in order to be heard and to have expressive choice in the quality of the sound.
On the other hand, there are different tonal ideals and ways of articulating that become standard practice within a musical genre. In classical singing there is less freedom of choice because the singer has to be heard without amplification. In popular music the range goes from whispering to screaming, and everything in between.
My personal guideline is to never make a stylistic choice that cannot be technically executed without damaging the voice. Even more important to me than style is that every voice has a unique physical structure, housed in a very unique body and governed by a singular personality. The most successful and influential artists seem to be those who break the rules of whatever musical style they are singing in to bring something to it that has never been heard before, something distinctive that changes the way we listen and that inspires us. The best do it in a way that honors physical function and that allows them to have a healthy voice for an entire lifetime of singing.