However, we can look at how much additional GDP is added for each newly-borrowed dollar. This is called marginal productivity of debt. This shows a clear picture, a secular decline over many decades. To produce this graph, take change in GDP divided by change in debt.
I encourage you to read: https://monetary-metals.com/falling-productivity-of-debt-gold-and-silver-report-15-oct-2017/
Add to the above this concerning article on the lack of US savings: