Fiat money has properties which your proposed "stablecoin" doesn't, like a reason for people to wish to receive it as payment in the first place (people need to settle debts and tax payments denominated in that currency) and a central bank which acts to reduce the amount in circulation when inflation gets too high (Venezuela's central bank isn't doing that and you've noted the result...).

Incentivizing spending rather than hoarding just means you hit the lower bound (probably zero, unless receiving units of your coin is really, really technically interesting to some people) earlier...