The gist is that Portland drivers couldn’t stop hitting crucial safety infrastructure (proving its necessity) so PBOT gave up on it.
As one of the commenters pointed out: Since a pedestrian/bike fatality costs PBOT nothing and replacing a concrete planter a car has demolished costs them more than nothing, to balance the budget they’re going to go with more pedestrian deaths.
Stopping with 30 kph puts a pressure of over a metric ton via the seat belt on your body for a short time.