You are stating this like it's a fact and a known quantity but the reality is that it isn't.

Many countries who manage their money supply have wildly unstable currencies. Turkey for example.

On the other hand many economists belive Nobel Prize winner Milton Friedman's assertion that "Inflation is always and everywhere a monetary phenomenon" (more economists disagree with this probably, my point being that these are not settled matters)

And we have absolutely zero long term evidence of how currencies with pre determined supplies behave.

So, sure, state your case, you might be right, but don't make it out to be like this is some law of physics.