Alcohol detox is the only substance detox that can kill you.
However, it is much easier to overdose on heroin than alcohol, making acute heroin deaths, especially in young people, an issue.
I think the difference in perspective comes from:
1) the age of the people dying. Alcohol abuse usually kills you when you’re older. Teens and 20s are dying from heroin overdoses, making folks more sympathetic.
2) the perceived addictiveness of either drug. Most people still feel like alcohol is a choice, but believe that street drugs are so addictive that one use can make someone addicted.
3) the perception that heroin users started out as legitimate prescription drug users and accidentally got hooked, making it their doctors fault and not their own.
That’s all I got as far as theories.