No Stupid Questions

I'm not convinced, considering the US and many other countries with high standard of living are also leading the world in external debt (both total and per capita).

https://en.wikipedia.org/wiki/List_of_countries_by_external_debt

Maybe you mean debt to GDP+wealth ratio? Or more specifically, bad credit with international banks.

I'm not an economist though, so I'd be curious to hear if there is more explanation for why you consider debt to be "the main reason."

I am aware that some countries have been "screwed over" by large banks that had specific detrimental stipulations for debt forgiveness though. For example, look at the Latin American Debt Crisis.

...the Fed convened an emergency meeting of central bankers from around the world to provide a bridge loan to Mexico. Fed officials also encouraged US banks to participate in a program to reschedule Mexico’s loans (Aggarwal 2000). As the crisis spread beyond Mexico, the United States took the lead in organizing an “international lender of last resort,” a cooperative rescue effort among commercial banks, central banks, and the IMF. Under the program, commercial banks agreed to restructure the countries’ debt, and the IMF and other official agencies lent the LDCs sufficient funds to pay the interest, but not principal, on their loans. In return, the LDCs agreed to undertake structural reforms of their economies and to eliminate budget deficits. The hope was that these reforms would enable the LDCs to increase exports and generate the trade surpluses and dollars necessary to pay down their external debt (Devlin and Ffrench-Davis 1995). Although this program averted an immediate crisis, it allowed the problem to fester. Instead of eliminating subsidies to state-owned enterprises, many LDC countries instead cut spending on infrastructure, health, and education, and froze wages or laid off state employees. The result was high unemployment, steep declines in per capita income, and stagnant or negative growth—hence the term the “lost decade” (Carrasco 1999).

https://www.federalreservehistory.org/essays/latin-american-debt-crisis

Quoting myself here...

Here are some topics but NOT an exhaustive list:

Thought debt could go into some of the other categories. Calling it out individually or under a broader umbrella of economics would be fine, too. It's just a suggestion list for OP to research.