There have been dozens of those "clicker bats" for at least 20 years now.
The rationale behind is to prevent early unhinging.
The difference with this one seems to be you can use it with hard balls and not just dry swings like most clicker bats.
Personally I don't buy stuff like this but I often build training bats myself. I wouldn't spend that much money on a thing that the kid might use for two weeks and then never uses again