Could this lead to a shortage of "money" - which in turn limits production of essentials, like say food?
It's an interesting hypothesis but would take quite a lot of research to explore. It was a slave economy - so no money needed there. On the other hand perhaps non-slave workers were laid off, reducing production etc.
My gut sense is that it's not a significant issue. Conditions like drought and storms are more likely to have needle-moving effects. Food security is the root of stability and (as the article points out) there were periods of food insecurity towards the end if this period.
I'm also unaware as to the degree of currency production at this point (ie mining of gold etc which was what might be referred to as "wealth".)
The most obvious wealth of course is land, and that can't be sold "out" of the economy.
I suspect you are pondering though to analogize it with today. Since the supply of physical money is not constrained these days, there's no real risk of unrestrained imports impacting of the economy. Rather the loss of primary production would be a concern (a metaphorical drought) . However primary production (food, oil, mining etc) seems strong. Secondary production (factories) are weak though. Which is probably a bad thing overall.
Certainly an interesting hypothesis though.
Also I think that the US and Europe are very different when it comes to concentration of wealth, and preserving that concentration. It is difficult to pin down why. For one, Europe is legally inferior in terms of the legal structures permitting early stage and disruptive companies. European countries are also biased toward favoring large employers in terms of preventing competition from former employees.
Ideally, you want a system where people who have generational wealth can lose it easily, as much as you want people who work really hard, and especially people who are extremely innovative to be able to catapult themselves to positions of consequence where they can determine good decision making.
Anyway, back to wealth flowing out. Europe in that respect might be the winner. LVMH and Hermes being among the largest companies in Europe by market cap, suggests the wealth is flowing in, even if Europe would likely prefer to be making money out of other less cyclical goods and services.
Do you though? I'm not sure.
Social mobility certainly has benefits, it motivates etc. Equally, it would seem advantageous for the weak-aristocrat to fall, making way for new blood.
Certainly we've seen the end of formal feudal aristocracy. The French Revolution started a wave of royalty-ending power. Today, while monarchies and aristocracy dukes, barons etc) still exist, they are not major factors. (With the exception of the UK where they lack political power but are still wealthy.)
The second generation of wealth, the industrialists, also wax and wine. Competition comes from within and without. Large brands have faltered, new industries have risen, and fallen, but social structures have remained solid since ww2.
There is clearly economic mobility, but wealth concentration seems less obvious in Europe (although a trip to Monaco might weaken my argument.)
What Europe has is a bit more discretion. Mysql, Nokia, Skype, etc and plenty more are, or were, European. But you don't see those founders in the press, and outside very narrow communities you don't know who they are.
Which I suppose brings me back to your point. I think you are correct, but I'd add that the stability of society as a whole acts as a good framework for that mobility. I'm not sure the American system of massive disparity is ultimately good.