All I know is this. People keep on saying the economic model of what the French people want isn't sustainable. Is the US model sustainable? From all accounts, nope. So what do we do? Go back to communism?
The funny part is, regardless of which social, cultural or economic model you want, the one that everyone hate is the inequality.
It could be stable in the US. The basic idea behind Keynesian economics is: during contractions, decrease taxes and increase spending; during expansions, increase taxes and decrease spending. Doing this helps smooth out business cycles, promotes steady growth, and collects revenue for the government.
The problem is, as we've seen, our government is cutting taxes and raising spending no matter where we are in the business cycle. That's a very easy problem to solve, if there is the political will, but right now, there isn't.
This offers nothing insightful or useful, and doesn't even address a fundamental problem. It's the sort of thing someone says when they don't understand a topic well enough to weigh in, but they still feel impelled to weigh in.
That's the issue with your post because you don't even understand the issue isn't an economical but a social. Again, don't pretend you know what you are talking about because of tiktok.
Tangentially related, read the books by the winners of most recent Nobel Prize in Economics, The Narrow Corridor and Why Nations Fail, and both filled to brim with essentially anecdotal examples with post hoc theories to argue with pop economics/historians like Germs Gun Steel author and others convincingly but essentially no actionable items to suggest changes for better outcomes except generalities. Piketty's Capital Ideology is similar in content but in conclusion he makes note of changes that would improve things, very hard changes to make but notes these systemic changes are needed to fix things with a democracy.
Are you talking about the financial situation or something else? As mentioned above the financial situation is sustainable indefinitely because the US controls the printing of the dollar. Other situations might be sustainable or not, depending on what you mean.
The funny part is, regardless of which social, cultural or economic model you want, the one that everyone hate is the inequality.