Why the increase in debt?

Between 1995 and 2023, total debt (household, corporate, government) rose from 177% of GDP to 243% of GDP in the United States, and from 178% of GDP to 235% of GDP in the euro zone. Why this sharp increase in total debt? As far as households are concerned, a major explanatory factor is the rise in residential real estate prices; as far as companies are concerned, the only explanatory factor is the increase in distribution of earnings to shareholders; as far as governments are concerned, the explanation is probably population ageing (due to the resulting increase in healthcare and pension spending). What part of this increase in debt is worrying and what part is not? The only part that is not worrying is the increase in public spending on R&D. The rise in residential real estate prices, the increase in the distribution of earnings to shareholders and the rise in the burden of pensions are worrying because they are not matched by an increase in productive investment and production capacity.