Elon Musk, the billionaire entrepreneur who founded Tesla and SpaceX, is famous for envisioning the future and moving technology forward. One problem he hopes to solve using this strategy is traffic congestion in major cities. In Los Angeles, for instance, the average driver last year spent more than 100 hours stuck in traffic. Many other cities also struggle with gridlock.

Musk’s solution, which he calls the Loop, is to bypass surface traffic entirely by digging tunnels underneath cities. His system would use elevators to lower self-driving electric vehicles (cars and larger bus-like pods) from the street down to a network of tunnels. Once underground, the vehicles would then speed along as fast as 150 miles per hour.

For anybody who ever sat in a traffic jam, this probably sounds almost as miraculous as soaring above traffic in a flying car. But can Musk’s plan work? And even if it’s possible, is the Loop really the best way to solve the problem of traffic congestion?

Some critics just don’t think the Loop can be built at all. Concerns about technical feasibility and cost have led some experts to warn that “physics and money” are not on Musk’s side. However, the only obstacle Musk sees is a lag in technology. Therefore he and his new “Boring Company” are developing faster tunnel-boring machines intended to make building tunnels efficient enough and cheap enough to make the Loop project viable. (The company is also taking other steps to cut costs and address past problems faced by tunnel builders.)

It’s clear that Elon Musk is an innovative thinker and adept with technology, but what if traffic congestion is not a problem that can be solved with technology alone? That’s the basis for many skeptics’ arguments against the Loop concept: traffic congestion in cities is usually about much more than just an engineering challenge.

One dimension of the problem that Musk may be overlooking is politics and public sentiment. The Boring Company already had to cancel a planned test tunnel it hoped to build in Los Angeles, due to a lawsuit by neighborhood groups. Imaging how many people and groups might work to delay or scuttle the project if an extensive network of tunnels is initiated. The Los Angeles Metro Rail, the closest thing L.A. has to a subway system, has struggled for years to expand even glacially, due to local resistance—and in that case we are talking about a known quantity: a system that is already up and running. A recent attempt to improve overall safety by altering traffic patterns in the Venice Beach area of L.A. has met with public outrage by people whose personal commutes were impacted. Between a prevalent “Not In My Backyard” (NIMBY) attitude and the intense scrutiny and vetting process required for environmental reviews and other bureaucratic hurdles, the same roadblocks that have prevented other proposed solutions from going forward seem very likely to plague the Loop as well.

Another dimension is logistics. Even if public support could be guaranteed, the success of a system like the Loop would depend on more than just being able to build the tunnels cheaply, or make the vehicles in them go fast. Vehicles would still need to get in and out of the Loop via Musk’s elevators, depicted in promotional materials as curbside platforms no bigger than a couple of parking spaces. However, in a city like Los Angeles, people routinely fight over parking spaces and some of the gridlock Musk is trying to alleviate results from long lines of cars waiting to get into parking lots, get onto freeway ramps, or simply make turns. This suggests that accessing the Loop will likely to be a lot more complicated that it looks in the Boring Company’s videogame-style demo videos. Bottlenecks to get on and off the Loop’s underground automated freeway could end up negating whatever time is saved by high-speed travel, once cars finally make it down into Musk’s subterranean tubes.

Musk also does not seem to be taking into account the phenomenon called “induced demand.” He has claimed that more and more tunnels could simply be added to the Loop as needed, to keep up with demand. But it turns out that adding extra lanes and new highways does not actually decrease traffic congestion; instead it opens the way for more traffic and ultimately the same amount of congestion (or more). That’s because the temporarily increased mobility just encourages people and businesses to rely on driving more. This suggests that Musk’s seeming futuristic vision may actually be surprisingly short-sighted.

Finally, there is the question of inclusiveness. Who is the Loop for? Musk came up with the idea while stuck in traffic himself. Like any frustrated driver, he daydreamed about a way to spare himself the hassle of getting caught in rush hour. But coming up with a plan to help some commuters personally avoid delays is different from coming up with a plan that helps everybody. It is like building luxury condos when people are homeless; instead of solving the problem, it provides a place where a minority can avoid looking at the problem. Many critics therefore believe that the Loop is ultimately just a distraction from finding real solutions to the problems faced by big cities.

Those problems include poor air quality, lack of public space, and streets that are dangerous to pedestrians. Traffic congestion aggravates all of those issues, and solving it will require more than a “workaround.” We have to think about making fundamental changes in the way we design cities, and in how we live, work and get around in them. We have to be willing to make sacrifices instead of fighting against changes that threaten our routines. We have to consider the welfare of all citizens instead of only focusing on our personal preferences. Just like with fighting global warming, we have to be willing to change the way we think, and even our values. If people consider riding alone in a luxury car to represent success, and riding next to their fellow citizens on public transportation to represent failure, then just providing more buses won’t be enough. We have to consider whether we have built cities for cars instead of for people, and how we can change that.

Of course, getting people to change the way they think, on a large scale, can be more challenging than any engineering problem. Elon Musk has accomplished some amazing things, but as a culture we have become a little too obsessed with genius inventors who will save us (or at least provide amazing new gadgets). The truth is, sometimes there is no quick fix—only hard work.