The worst part of the debt is that nothing good was done with it.
If you use that money to implement a national healthcare system, or fix the national infrastructure, or stabilize social security, or figure out child care, or work on affordable housing, or fix the cost of education, or invest in renewable energy, etc. then maybe it's worth it. Hell, you might even end up net positive in the end with all the good done to society in the long run.
Instead, all of these things are even worse than before while most of the money was spent on a bunch of useless wars and tax cuts for the rich.
And now, there's no more easy money to be borrowed to fix anything.