> This "cost" is manufactured
It's not manufactured. They are making promises that have a net present value of X dollars. That's a real cost they are incurring and it has to go on their profit/loss statement.
>Up until 2006, the USPS funded those obligations on a pay-as-you-go-basis,
No company is allowed to do that. All companies are required to fully fund their pensions:
>The funding requirement under PPA is simply that a plan must stay fully funded (that is, its assets must equal or exceed its liabilities). If a plan is fully funded, the minimum required contribution is the cost of benefits earned during the year. If a plan is not fully funded, the contribution also includes the amount necessary to amortize over seven years the difference between its liabilities and its assets. Stricter rules apply to severely underfunded plans (called "at-risk status").
https://en.wikipedia.org/wiki/Employee_Retirement_Income_Sec...
> But it probably would've spent at least part of the last decade making comfortable profits.
You have to keep cash flow and profit clear. The prefunding requirement does not change their profitability. It changes their cash flow.
> If the prepayments required under PAEA were never enacted into law, the USPS would not have a net deficiency of nearly $20 billion, but instead be in the black by at least $1.5 billion.
Again, not in the black. They would have $20 billion dollars more in the bank but they would not be profitable. Simply put, they'd have a larger pile of cash to burn before the day of reckoning came.
An analogy would be someone jumping off a very tall bridge. They're dead the moment the feet leave the bridge. Saying that they would survive longer if they jumped off the top of the bridge is technically true but doesn't appreciably change anything. They're still dead. It will just take a bit longer and the splat at the bottom will be more impressive.