I think when Johan says it's more of a Vicky thing, it's "for the majority of the game it didn't happen or wasn't common at all."
The House of Commons has existed since the 14th century, but I wonder if that means just representing the Peasants with a privilege that allows them to interact in the Parliament.
I mean, political parties were a thing, at the very least if you consider the Federalists, Democratic-Republicans, Whigs, Tories, and the Dutch Orangists and Statists political parties or rather cohesive factions. Still, I'm not sure we all expect political parties to be in the game unless it uses EU4's factions or something.