I remember wires boinking out from under terminal-strip screws,
It might just be something around my area or the era in which I was born but I don’t see how a conductor could bonk at all. I think this was intended by our creator to be done between husband and wife in order to keep their gene pool alive.
while doing controller low-voltage wiring, but it seems that sort of thing isn't possible on a modern electric receptacle, given their geometry.
As Don pointed out, this is mostly due to improper installation just as most failures in electrical systems.
When I was going to school and studying electronics we were still working with vacuum tubes so this should tell you that I went to school many years ago. Yes I am familiar with modern technology but that is not the point I want to make.
Way back when we were still cutting trees to build the Ark there was a rule and a firm rule we followed that seems to somehow fell by the wayside, tin first. Yes I know that many in the low voltage today don’t even know what I am talking about but I bet there are many here that have a full understanding of that comment.
As to the geometric make up of low voltage terminals verses those on premises wiring devices there is one very major difference. The major difference is the amount of foot pounds mandated for the amount of pressure that holds the conductors in place and the type of conductors being held in place.
In the premises wiring of our homes the smallest conductor allowed is 14 but in low voltages we can use as small as 28 gauge conductors. In a lot of cases these small conductors are stranded and use a fine strand in the manufacturing process. Fine stranded conductors are harder to hold in place than solid conductors and this is the reason the NEC mandates that when fine stranded conductors are used the terminal used has to be listed for stranded conductors. We see the fine stranded conductors in photovoltaic more than any other place.
Now couple improper terminals with any human being and we have the equation for failure. Why you might ask. Well as humans we learned a long time ago to add erasers to our pencils for one reason or the other but I think it is because we aren’t perfect. Get my meaning?