For those who don't appear to know what "Tragedy of the commons" is, it's an economic concept[1] that doesn't necessarily involve a "tragedy" and "the commons" can include private property.

A recent example of "tragedy of the commons" was during the recent California extended drought, Wall Street firms were buying up struggling pistachio farms in California, drilling wells deeper than nearby farmers did, and were undercutting those farmers by siphoning the aquifer from below, encouraging those competing farmers to dig deeper wells and use water faster. "The commons" would be the aquifer / water rights that the farmers commonly depend on. The tragedy was that in the depths of the drought, other pistachio farmers were unable to afford to dig deeper, their harvests were scant, and the price of pistachios worldwide had tripled -- all of which further incentivized well funded outsiders to do the same and buy out farmers.

You can argue that SF MTA management and SF building / zoning policy isn't in the best interest of SF citizens, but pedantically arguing the semantics of "tragedy of the commons" won't win you any intellectual arguments.

[1] https://en.wikipedia.org/wiki/Tragedy_of_the_commons