It takes me about 2 days to sync a Bitcoin node. Can't speak for Monero. Opening a bank account isn't equivilent to being able to audit the entire history of the money supply though. I could download a wallet faster than I can open a bank account.

It's the standard argument that economists make about why inflation is a good thing. Wouldn't want food prices to drop and benefit the people bcause that would lower corproate revenues, result in job loss, and lower a nation's GDP. We must have two percent "inflation", enough to keep people working for most of their lives, but not high enough for them to complain about it.

Creating an abundance of money can create scarcity elsewhere (too much money chasing too few goods). Wealthy people and big corps are the ones that will overwhelming receive new money (via credit creation) and they won't need to buy extra food with it. They'll purchase hard assets. Real estate, stocks, etc. Stuff that is not tracked in the CPI buckets.

If the population decreases, I don't think we're going to see the number of monetary units go down for any significant amount of time. The collateral values will decrease and the system blows up. The only option is to keep the collateral prices elevated with more and more debt creation.

Money supply management is often exhaggerated too. Far too much power is attributed to the US Fed. They have some control on short-term moves but the eurodollar/offshore banking system accounts for a massive amount of dollar creation which is outside the purview of the Fed. They admitted long ago that they don't even know how to track the money supply anymore.

I wouldn't suggest abandoning the existing system in a disorderly fashion, but there will always be someone who thinks they can manage it just perfectly. If Bitcoin continues to grow in adoption, money flows out of the existing system and into a completely different one.