We were on metal standards for millenia. Governments routinely spent beyond their means, including for imperial aims. This is like four centuries of Roman history.
"In the second century, a modius of wheat (approximately nine liters), during normal times, had sold for ½ Denarius…. the same modius of wheat sold in 335 AD for over 6000 denarii, and in 338 AD for over 10,000" [1].
Note that inflation can also occur with zero debasement if the economy around the fixed money supply collapses. This happened in Rome when Pompey and later Augustus were trashing trade routes. It may have even led to the collapse of India's ancient democracies.
> there were serious political repercussions for it
There weren't. The state historically borrowed from the hilt of the sword. Economic collapse constrained kings and emperors. Not politics.
[1] https://etedge-insights.com/featured-insights/analysis/how-h...
You're hitting the nail on the head. Metalness didn't matter. It was competition in money supplies (and strength of private property).
The fact that a banker in Italy could finance (or not) a war by Great Britain is what restrained governments. Same as in the 1990s, the bond market was king.
The historical record simply does not support the hypothesis that metal-based economies are more peaceful or inflate less than modern fiat-based ones. I'm open to revising that opinion if someone has re-run the data. But everything I've seen comes from blogs that start with the conclusion, itself reached from assumptions from first principles that rarely contemplate how armies were actually financed in antiquity. (Hint: they take your shit. Marketing campaigns sharing the martial term isn't a coincidence. If you're a general in the olden times, you got wealthy through your commission because your army took the enemy's shit. If you needed help getting there, you paid a 'friendly' visit to your nobles.)