No instead he can make a crock pot bomb & hit a crowded public event. He can run his car into a crowd of people. So yes he can still do terrible things.
Okay. THe Crock pot bomb killed 3 people. That was bad and all... but not nearly as bad as your average mass shooting.
Just because we can't fix ALL the problems, doesn't mean we shouldn't fix this one. We've had 216 mass shooting so far this year. You have to go back years to find someone who made a crock pot bomb.