Correct. There's a few other internal safeties to help ensure it doesn't go off unless someone is pulling the trigger and (hopefully) intending to fire.
It's still drop safe and not going to go off by itself, but if you fire it (and there's a round in the chamber), it's going off.
>As a non-gun-person that seems like an insane design decision
There's certainly tradeoffs. It's simpler and you're not going to accidentally forget to disengage a safety at the worst possible time (when you actually need to be using a gun), but it does increase the risk when improperly handling the firearm which is a risk not everyone is cool with for obvious reasons (and even experienced operators (incl. Law Enforcement being generous, which largely carry Glocks) are human and can make mistakes).