"We'll simply create a perfect dictator and put it in charge."

There is no such thing as a good dictator.

It's impossible.

The problem with a dictator is there is no room for error.

If there is any error, there's no way for the system to self-correct.

But nothing is infallible.

Imagine you thought other parties were going to try to make a perfect dictator oracle, and they just might succeed.

Now you'd be locked in a race to make a dictator for the human race, because yours would be a good one, and the competitors' would be the bad one.

Everyone thinks their own candidate is intrinsically good, because they created it.

An infinitely powerful dictator is a winner take all, so it becomes a totalizing quest to install yours first before the baddies do.

An emergent arms race to install a dictator.