This is kind of like comparing machine guns to automatic weapons. They are both illegal, and both deadly, and exist on our streets in concentrations that sometimes make our efforts to stop them seem fruitless.
Since both of these drugs are illegal, this also means they are illegally manufactured, with no standards for quality control or purity, so that users of both drugs do not have any idea what chemicals they are putting into their bodies. This makes using either drug extremely damaging and high risk.
Methamphetamines, however, tend to be more addictive than cocaine to many users, and the timeline for self-destruction in one's personal life and in their health is shorter.