I always have trouble with essays using accumulation of debt as the proof of systemic unsustainability. Debt is a construct made up on an agreed upon monetic system and the associated trust placed in its repayment, it's not a physical dimension that can be used to derive proof of sustainability beyond system itself. It can easily be changed, notably by printing money or forgoing debt.
While that is true on a higher level, individual cities don’t have tools like printing money or ultra-low interest rates available to them.
If you have a look at how municipal debt is rated, you’ll see that the rating agencies rely on projections of growth to determine how creditworthy a city is. It’s of paramount importance to spend borrowed money in an efficient way if the city expects to borrow more in the future.
debt is a promise made by some entity to another entity. Any forgiving is going to require the promise to be broken, or altered. So somebody gets the short end of the stick.
Printing money is similar, but instead of the entity lending the money taking the hit completely, the "loss" is spread out through all money users.
Neither is good - but sometimes it might be the only good option.
