but not tall enough to be seen by the drivers
They’re the height of a child and also high-vis yellow. You need More Proof someone’s not paying enough attention to pilot 2 tonnes of metal?
someone’s not paying enough attention
That’s one way of looking at it.
Another would be, its evidence of bad vehicle design & inadequate visibility from the driver’s seat.
One thing to note is that if the vehicle being driven wasn’t an SUV, that bollard would have easily been seen through the rear view mirror. Looks like the bollard is ‘just’ low enough to stop below the top of the rear seats. SUVs bad.
I believe that all cars sold in the US since 2016 have been required to have back-up cameras.
Those are only situationally useful. They tend to be too dim and blurry, and if you’re wearing polarized sunglasses they can be totally black. Focusing on them long enough to make out what they’re displaying causes tunnel vision - you can’t really shift your focus from looking around out the windows and back to looking at the screen fast enough.
Back-up cameras are great for measuring the last couple inches of parking.