There is more currency every year because of inflation, which means more available to pay back the debt which is growing slower (in this scenario). Imagine being on the other side of this, you are earning interest on your treasury bonds and planning on using it to buy gas for your car, but in 2027 can buy less gas than 2026 because you got ripped off by the government indirectly.
One problem with this is, at some point people may realize loaning money to the government is a bad deal and stop doing it.