Couple of questions:
As Trump said, they’re not send their brightest!
People can climb bollards, with the same technique used to climb coconut trees. Fit young men have been scaling the 18 foot bollards like that, carrying loads of drugs on their backs.
I think that scale of this fence, is what defeated this guy's attempt. If your arms or your grip wears out on an 18 foot fence and you slide down, you walk away (probably without a limp). But arms and grip must be significantly stronger/fitter for a 30 foot barrier (beyond the average man in the street), and a slip could mean death or permanent disability. At the top, 30 feet can be dizzingly high - a lot more fear-inducing than 18 feet.
They need to start putting the barrel tops on these bollards, to keep free climbers off the dangerous tops of these barriers. Congress forbade new designs in the last appropriation, but they should require these anti-climb "Safety Tops" from now on.