Without further ado, and in no particular order, I present the five most culpable professions for broken cities and the infrastructural debt accrued.
1. Engineering/Road Building companies and lobbyists - Biting the hand that feeds them maybe? One irony is that there would still be work (and still is) in building proper cities at lower (affordable) levels of infrastructure per capita, but that would mean much smaller projects and therefore fees. Building the unsustainable also means that all that infrastructure will (is) fall(-ing) apart and need to be rebuilt.
2. Urban Planners - Idealists, one and all. We like to quote Jane Jacobs but forget she was observational not an idealist. One generation's "pop-up urbanism solves all problems" (which it most definitely does not), is another generation's Euclidean zoning. Everything is done with the best of intentions, but rarely do they understand processes behind urbanism and too often focus on the physical representations: "Live above the shop! Mixed-use! Street Trees!" Et Cetera. Each outgrowths of deeper forces and in some cases even visceral and psychological. That deep. Those emotions drive markets. The infrastructure and codes are tools enabling (and too often disabling) those interactions.
3. Transportation Planners/Engineers - You didn't think I would leave this one out did you? Always concerned with moving cars with little regard to side effects or without a higher purpose. We gotta move cars. Why? Cuz we said so. That's efficient. Nazis were also efficient. Had pernicious spin-off effects too. Cities are complex organisms comprised of competing, overlapping, complementary, and compromising needs. Letting any one particular issue (besides basic law and order) dictate everything else, well, what you see is what you get. Especially when the answer to every question is more supply. That's not being a professional. That is Homer Simpson's dipping duck.
4. Politicians - Somebody has to take that lobbying money right? They also have to believe wholeheartedly in the ponzi scheme of Keynesian style road building leads to something called growth. It did, once. At some point, it surpassed a tipping point where accommodating demand gave way to just building supply for supply's sake. Homeownership! Even if the ends and means are corrosive. It also gutted the cores of cities and corrupted the ability of those areas to maintain themselves.
5. ??? All leave the last to crowd sourcing. As with all groups, there are the well-intentioned, the heroes fighting the good fight, and those just collecting a paycheck. The list tells me that the entire system of decision making and city building (and financing) is profoundly broken and any and all professions even quasi-related could find themselves on such a "blame game" list. It really isn't any one person or profession's fault. We are all complicit and it is in all of our best interest to rethink our profession and cities from the bottom up. Questioning.
Institutions, one and all, are the greek gods of our day, striking us down if we dare rise up against them. They resist change, feeling profoundly threatened by it. And in some ways that fear of leaving the status quo is a good thing. Preventing change from happening so rapidly that it becomes dislocative. But at some point, if you keep driving the same direction you're going to drive off a cliff. Sometimes it is best to stop and ask directions.