Why do you think otherwise? He was very clear about it long before DOGE. He viewed the debt as an existential threat to the country and believed Trump was the only candidate that might actually fix it. Looks like the joke was on Elon.
I just don’t believe Musk has any ability to reason about things from a rational perspective. Some of the best work done to address the US debt has occurred under democratic leadership, while time and again we’ve seen republicans balloon the debt.