Palpatine did NOTHING wrong
The Jedi are sexually repressed holier-than-thou hypocrite cultists with a stranglehold on the galaxy, while pretending to be peaceful monks.
The Republic is a weak bureaucratic mess.
Palpatine corrected both of these issues by removing the Jedi from power swiftly, and by reforming the crumbling Republic into a glorious Empire.
There is literally no argument that Palpatine was anything but the protagonist of the prequel trilogy.
In all honesty, the Jedi were dicks and the republic itself was rotten to the core
The Republic was a huge, corrupt, inefficient mess. But the Empire was, quite literally, Nazi Germany in space.
Of course Palpatine was the antagonist. That is clear by looking at his position in the original trilogy as the antagonist, as “Space Hitler”.
Plus, the Galactic Empire was modeled after Nazi Germany, and Palpatine’s story parallels Hitler’s rise to power. Palpatine was nothing but a scheming, evil man.