In Austria a big reason are old rural rail lines. It’s not trivial to install automated gates without having to remove some stops or keeping the gates down for very extended periods of time.
They are also not entirely safe because people are idiots and get stuck without understanding that they can actually push through the barrier.
Ones with nothing except signs to stop, look and listen. You're most likely to find this while hiking, as a footpath crossing.
Flashing lights and beeps.
Half barriers, which only cover half the road (one lane in each direction). These are my automatic. Drivers can't get trapped.
Full barriers. These all have CCTV, and the train won't get a "green" until the signaller has seen both barriers close, and that no one is in the middle. These are used in cities and other busy places.
One other fun type are the user operated gates. Normal farm gates on both sides of the railway, with a red/green aspect light telling you if it is safe to open the gate. Once you've driven through you have to stop and then close the gates. Last time I used one of them, by the time I walked back to close the first gate the signal had gone red so I waited.
We also still have some full barrier crossings operated by a signalman near me. There's something pleasing about that.
They are also not entirely safe because people are idiots and get stuck without understanding that they can actually push through the barrier.