I don't remember any time in which Trump or any supporter said they thought he would eliminate the debt.
IMO he won simply because his opponent was Harris, a candidate so bad that nothing she supported eg abortion, war in the M E, being "black" and female ergo supporting blacks and females over white males, and so called "green" policies was enough to even win her the popular vote. She did worse than Biden with Latinos, Blacks, women, Muslims.