There’s really no need to have aluminum bats. I understand they are more durable than wood bats, but they are more dangerous.
They don't sound the same, but I never broke one (sharp ends and all that).
I don't see them as any more dangerous than a kid who can really wallop the ball.
The rest is up to the reaction time of the defensive players.
You might want to ask Steve Yeager about how safe wood bats are.
John Grisham has an interesting take on this controversy in his book “The Appeal”
I think the solution is composite bats carefully tested to match the performance of baseline wood bats. I agree aluminum bats are a bad idea.