No the 70s and 80s were all about blaming poor people for crime. I was a teenager when the ban on leaded gas started happening and I can’t remember anyone ever mentioning the effects of lead as a driver of crime. I do remember discussing it in science class, but it was just starting to be understood at the time that lead exposure could lower your IQ and was around that time that the “no safe levels of lead exposure” was established. Before that it was just one of those things you had to be careful around. It wasn’t until well after the crime rate started to drop so dramatically in the 90s that people went looking for the reasons why