It was also the climax of years of deeper issues for the Metro: A unique stew of declining ridership and chronically unsafe operations, all rooted in troubled leadership.

But, the Metro’s own problems aside, the shutdown offered important lessons about transit nationwide.

The most surprising is that for many, the shutdown was a manageable inconvenience, not the disaster that Twitter dubbed #metrogeddon. Though there were conflicting reports, the Washington Post reported that during the shutdown, “traffic was not much heavier than usual for a Wednesday,” largely because so many people worked from home. That suggests many more people could be telecommuting than do now—not just in D.C., but everywhere, saving huge amounts of time and money.

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Those who didn’t opt to stay home had several options besides driving. Uber and Lyft, for instance, offered rate caps and incentives to attract more riders. Uber, in particular, boosted the coverage of its carpooling uberPOOL option, feeding substantial ridership increases.

The city’s bike share system saw double the normal number of single-day users. Neither of those systems existed before 2010, highlighting that cities are gaining redundancies to deal with even major transit disruptions.

But telecommuting, driving, Uber, and even bike sharing aren’t blanket options for all commuters. Those in the service industry, in particular, couldn’t stay home. Many lower-wage workers don’t have cars or even cab fare. There’s growing evidence that bike sharing systems don’t do a good job of serving the poor.

On Wednesday, many workers were left relying on D.C.’s bus system, which was widely reported to be jam-packed and delayed.

Transit debates often focus on getting drivers onto trains and buses. But the Metro shutdown was a reminder that for many of the essential, hands-on workers who keep a big city running, public transportation is the only option. When transit isn’t efficient or accessible for those workers, it imposes a so-called “commuting penalty,” making it harder to get to work and eating up extra hours over the course of a week compared to higher-income workers.

That fact ran head-on this week matched by another factor: American transit infrastructure, much like its highway system, is reaching its golden years. D.C.’s metro opened in 1976, making it a relative youngster compared to New York’s subway, opened in 1904, and Boston’s rail service, which dates to 1897. Compared to the next-generation metro systems arising in the developing world, America’s busiest systems are constantly being repaired and upgraded, causing chronic disruptions.

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That D.C.’s uniquely beautiful and modern Metro has faced the same problems as much older systems seems to be a product of profoundly dysfunctional management. Even as the Metro fell apart in recent years, billions of dollars of allocated funds went unspent due to administrative failures.

That feels particularly egregious when the rest of the country is facing a $1 trillion infrastructure gap, which includes shortfalls for transit and highways.

That makes D.C.’s Metro problem a less dire version of Flint’s water disaster—a canary in the coal mine of America’s declining infrastructure as well as a clear illustration of the impact of neglect on a city’s prosperity and citizens’ happiness.