No, we see the consequences that it causes in young people: The loss of sense of priority, the loss of capacity for independent discovery and the judment of reasonableness, the disruption of normal thinking (leading to making things up, to outright paranoia and psychosis).
Without commenting on how likely it is the hypothesis is true, the lead-crime hypothesis has always been academic handwaving to make a different, political point.
It causes long-term loss of IQ, and it is the main suspect for elevated crime levels in the lead-crime hypothesis: https://en.wikipedia.org/wiki/Lead%E2%80%93crime_hypothesis