A barrier in midair isn't going to be too much more obvious than the bright red signs on either side of the road saying cars aren't allowed, and in some places will likely end up getting damaged and costing more to maintain. A fine sticks in your mind for a while, but causing £400 of damage out your own stupidity is going to stop you ever doing it again.
I agree its a daft risk to the baby in that video, and indeed to any passenger of the car espically if they're young, but its clearly the driver who decides to take that risk into his own hands. In every incident in that video the driver was clearly aware of the bollards and thought they knew better and to risk it. To be honest if someone has such little respect for the law, and sod all common sense why are they on the roads endangering other people? And they came off on the short end of it, while endangering other people. They do the job they're ment to perfectly, without IMO unnecessary risk, and you notice in all 3 incidents the bollards stopped raising when they met resistance.