I understand why people would buy into the govcoin garbage but such a coin would lack any true value. Sure the coin might be more stable, but the stake-holders have zero control of the coin policy, just like they have zero control of USD, etc.
Who cares about having a dollar on the blockchain? The only real benefit is to the government is they can spy on your money easier. They now can know everything you buy. The paper dollar has better privacy.
Since it won't be decentralized, it loses the properties of being corruption-resistant. They can change the coin on a whim. They can change the production schedule on a whim. These people think they can control the world. And the world keeps proving them wrong.
You can worry all you want, but such coins can only provide convenience. Even then you lose desirable properties of the current currency in that the paper dollar is very hard to trace.
Don't get me wrong, people will invest in it. But at some point, a black swan event will occur and fragile-coin will look like a bad idea.