Yeah, buying one fewer F-35 barely moves the needle on total cost, it just bumps up the per-unit costs of the project because its almost all fixed, not variable, costs.
I’m sure this is true, but “buying one less f35” to me sounds like shorthand for “don’t spend such a stupid amount on the next boondoggle military project”. I assumed it was a given that money had already been spent.
That's exactly what they've done. When you read about how the costs have come down or been kept stable, that's an accounting fiction where they increase the number they're "buying" so that the unit cost comes down.