Prior to the destruction of Carthage the “dictator office” seemed to sort of work for the Roman Republic. After the destruction the Republic was awash with wealth, so later dictators surrendered power with increasing reluctance (Thinking of Marius, Sulla finally Caesar!) until finally Caesar Julius & Octavian (Augustus) said to themselves, ‘What the heck I’m keeping it all!’
Anyway that’s my interpretation! Also there was only one Cincinnatus! Find someone today who even knows the story of Cincinnatus. At the time of the Founding Fathers it was a well known story for even the most commonly educated.
Yes, as in the US, Roman institutions were eventually corrupted when Rome was finally safe from other nations.
George Washington and everyone else knew that by stepping down from command of his Continental Army and returning to his farm, he was the 18th century model of Cincinnatus.
FDR did little more than any good dictator would have done, but being the President, whatever he did set precedent, which was condoned by congress by the acquiescence.