At the moment we have a monetary system that's a debt based monetary system. In practice this means that many people are operating under the assumption that someone's liability is someone else's asset, I think this assumption is rather systemic at the moment. Beyond a certain level of indebtedness a rise in interest rates triggers off a chain of defaults and that can cause a situation of credit contagion. An uncontrolled credit contagion event could very conceivably destroy the financial system. Much power is currently held by creditors and they will likely try to fight any attempts to change policy in such a way that reduces their power.

Here's a much more long form article that talks about the dynamics in play: https://desogames.substack.com/p/the-problem-is-too-big

Debt levels being high means that a significant portion of the revenue is there to service the interest payments and the remaining is not enough to cover all other expenses. Therefore you either raise more debt, or default.

Simple. As your interest increases, sondo your payments as a % of taxes

At some point, if interest payments are too big of a slice off total spend, investors will start believeing the debt will never be repaid... And thus monetise debt instead.