Isn't this problem unrelated to cryptocurrency?
There will be the US dollar, and the people involved will be incentivized to keep its value high, e.g. by pressuring or invading other countries to prevent them from switching to other currencies. Or they'll be incentivized to adopt policies that cause consumer and government debt to become unreasonably excessive to create a large enough pool of debts denominated in that currency that they can create an inordinate amount of it without crashing its value.
Or on the other side of the coin, there will be countries with currencies they knowingly devalue, either because they can force the people in that country to accept them anyway or because devaluing their currency makes their exports more competitive and simultaneously allows them to spend the currency they printed.
If anything cryptocurrency could hypothetically be better at reducing these perverse incentives, because if good rules are chosen at the outset and get ossified into the protocol then it's harder for bad actors to corrupt something that requires broad consensus to change.
But with crypto they do. See for example all the BAGS coins that get created for random opensource projects and the behavior that occurs because of that.
Creating your own chain just because you can rather than because you actually have a reason to implement the technology in a different way than anybody else should be disfavored and viewed with suspicion.
ERC20 tokens are part of Ethereum (and yes I realise there are also non ETH based tokens and that the gas cost of Eth makes them attractive etc etc)
Utility tokens are fundamentally equities and you need to firewall equity from an organization the same way companies in most market economies are regulated.