I don't see any major harm but I don't see any benefit either. In fact you can currently choose from many global currencies now including the Yen that has deflated over the past decades.
Not really. We have this thing called technology, which allows people to automate things. And it is very much possible to automate almost everything related to currencies and payments.
If merchant wants to hold currency A, but can gain customers from currencies B, C, D, F, he can just implement some payment processor which does all the legwork for him with 1% fee.
> I don't see any major harm but I don't see any benefit either.
It is pretty difficult to see benefit why someone would want to use for example dollars compared to euros. It is mostly where you happen to live and to what currency you are used to. But I would bet my ass that people would after all like to decide themselves what currency to use, instead of someone else to force them to use specific currency (however still most people would probably just use the currency they are used to).
It gets really complicated quickly and for most people best just to get the one most aligned with their costs/spending and then they can enter currency speculation if they want to.
And besides, sellers will want to use deflationary currencies, because then they raise prices without changing the nominal price. Therefore no one would be able to use a inflationary currency.
There already exists global competition between fiat currencies... The competition exists but the competition has bery high barrier to entry.
> And besides, sellers will want to use deflationary currencies, because then they raise prices without changing the nominal price. Therefore no one would be able to use a inflationary currency.
Nope, seller doesn't care if the conversion process is painless. Almost all sellers on the internet accept any currencies - for example, US sellers accept euros without knowing that they accept euros. Payment processors do the conversion.
In the end, the thing that matters is what kind of currency each participant wants to hold. If the buyer wants to hold currency A and seller currency B, they both can still do trade, if there exist somewhat efficient market between currency A and B. And there probably exists, currency markets are probably the first thing to evolve for any kind of usable currency.
