That’s irrelevant. While attempting to kill someone is considered a worse offense their both harm.

To be more clear, the amount of harm harm intended is the only difference. Manslaughter is still illegal even if the penalty for murder is higher. The difference is simply in the degree of harm intended not in the lack of intent to cause harm. If someone dies through because say you happened to have parked a normal car in a normal parking space then that’s perfectly fine, but kill someone because you where speeding and that’s your fault.