That can be broken down to motorcycle on the freeway (light traffic) vs congested city vs N traffic lights vs curvy mountain roads, riding around sunset, etc.
Knowing how dangerous something is in aggregate is not as useful as the specifics.
Those who are will more likely have a false sense of lower risk than their actions would subject them to. Those who aren't might be scared away by a larger value than they would actually be subject to.
This could even become a self fulfilling prophecy where activities with high average micromorts will only attract people more willing to engage in risky behavior, thus inflating the tail of extreme behavior that causes most of the mortality, increasing the activity's average micromorts over time.