Is dynamic music appropriate for automobiles? (high levels of background noise)
Generally, music with little or no dynamics is better suited for listening situations with loud ambient sound levels because quieter passages are masked by the louder background noises. However, this cannot and must not be an argument in favor of only producing and mastering music for use in cars with noisy environments.
In this case it makes sense to use modern DSP chip circuitry which provide automobiles with a compression system which is speed-dependent. This is a promising field for the consumer electronics industry for bringing new car hi-fi products on the market. Dolby Volume is a technology that already exists for such a use.