There will still be kids slipping through. They also say it themselves:
Indeed.
So, what's more effective?
Reducing the scope of those seeking to commit such atrocities to a small fraction of those now, or hoping for improvement via symptom whack-a-mole?
If only there were other factors which could impact the highlighted systemic issues... perhaps Canada's notable single-payer healthcare system, social safety nets, etc. impacting the desperation and providing help?