I agree wholeheartedly, and while I agree with the message, I think we need to be careful where we place the "blame" and whom we need to "tell." City planners get it - but they're not usually the ones in charge of designing public streets. It's often the public works departments, city engineering departments, or even state or county DOTs responsible for street design. These are the folks most responsible who need to hear this information the most, and are usually the groups most pressured to make transportation decisions based on transportation model data and cost first and foremost.
Where city planners do bear responsibility is starting an educated conversation. In our professional lives, we often find ourselves "preaching to the choir" - we get it, but we need to educate not only our colleagues in engineering and public works departments, but also the citizenry.
City planners are trained to avoid imposing their will on the citizens for whom they plan - that was the mistake of the urban renewal-riddled 1950s and 1960s. Now, we're trained to communicate information to help communities and decision makers make decisions they can defend to their constituents. We need to show, not tell.
Bottom line - this is a big deal, and while city planners don't deserve the bad rap, they're uniquely suited to address the problem. Let's just watch our messaging.