“With a ladder and a grappling hook, it can be overcome. They better have frequent patrols and thorough surveillance.”
Ropes and ladders will likely remain as possible, but impractical methods of getting past this kind of barrier even with an anti-climb top. As they say, 50 foot wall, 51 foot ladder. 30 foot ladders effectively require a team, and there is a delay when using ropes/hooks.
The new urban bollard is installed with camera surveillance, lights, patrol road, and likely hidden sensor systems (alarms). Even though teams of trained climbers with equipment could get over almost any barrier, they will be more likely to get caught. The great bulk of people will just be be deterred by the obstacle.