The bells are essential unless we want a rash of deaths and/or injuries to doodle-heads who wander around with their noses in their mobiles. They're dumb, so the nanny state has to protect them from themselves.
I agree with the first fourteen words, not so much the rest although the "doodle-heads who wander around with their noses in their mobiles" oblivious to their surroundings are a danger to themselves and everyone else where ever they are and being anywhere near a railway is only coincidental.
There are a couple of level crossings I am aware of near Harden where there are no bells or boom gates, only lights, a fact which I discovered to my surprise. I am making an assumption that these are private level crossings and each appears to provide access only to a single adjacent home. Thus the public would generally have no reason to be using the crossings and the people living in the homes would presumably be well aware that there is only a visual indication that a train is approaching. They are a special case. I think there may have been a sign at the one of them which I was near indicating the lack of a bell warning but if there was I did not see it.
I discovered the situation one day when I was parked next to the public road across the tracks from the home using the crossing bells (as I thought) to give me a warning of approaching trains. I was sitting in the car when I heard an approaching train and looked across at the crossing to see the lights flashing.
The point here is that I was expecting an audible warning as that is the usual case and it did not come. Had I been standing at the approach to the level crossing then I would probably have been aware of the lights but only if I happened to look at them. Presumably if I were someone about to cross the tracks I would be more attuned to the situation and be checking the lights, or would I? But if I was expecting a sound then maybe not?
I realise that these crossings are a special case and not mainstream but the point is that if people are conditioned to expect an audible warning and it does not come it increases the risk.