This is not a detailed analysis of the economic situation of those countries.
You are misunderstanding the basic sequence of events. Under a gold standard, if you try to undergo a major war, you go bankrupt during said war or immediately afterwards. Virtually all of the countries you keep referencing did exactly that. I would argue that no society to date has ever managed to produce a sufficiently large surplus of productivity to support a major war. They’re ruinously expensive! And the deficit required will manifest itself either over a long period of time, as we see with most fiat currencies, or almost immediately as with a gold standard.
Now sure, a gold standard doesn’t prevent a country from doing stupid things. Again, it ensures stark consequences for doing stupid things. And not “some ambiguous time down the line, when our great great grandkids have to deal with it.” Soon. Soon enough to matter to the people making the decisions. Wiser heads observe this and try to avoid doing said stupid things, but if for whatever reason a nation decides to embark on a particularly stupid endeavor, they get slapped with massive consequences. In the short run. There is no panacaea against stupidity. A gold standard just reduces the time it takes for consequences to be faced (and the subsequent impact of those consequences).
Remember, if you’re an American, your tax dollars today are still paying for the Vietnam war. We’ve kept current on the interest payments on the debt, but never actually paid down and retired any of it. When the principle comes due on one bond, we take out a new bond to cover the old. In a vacuum, we could keep doing that forever because our interest payments aren’t coming out of an ever depleting gold stockpile, they’re coming out of money supply expansion. I mean, we now owe more money than the total M3 money supply and we’re not bankrupt.
And just so you don’t feel I’m dodging your question (which was asked without answering mine), you should check out the economic situation the countries that surrendered were facing. Lack of gold (rather, purchasing power, because the specific unit of account doesn’t matter as long as it can’t be materialized easily) is almost always the root cause of the collapse. Can’t afford your logistical requirements? Your army collapses, or you ration and confiscate from the populace and they collapse into starvation (Germany) or open rebellion (Russia) until your army then collapses. Abandon the gold standard so you have infinite money with which to afford these things? The people’s purchasing power rapidly evaporates, they can’t buy food, and they again collapse into starvation or rebellion.
WW1 was largely a race against economic collapse, which Russia, Austria and Germany most definitely lost. Unfortunately, history books only talk about the pew pew side of war, so much of the horror experienced by the civilian population is completely under the radar.