tbf the English Civil War is, like most Civil Wars, pretty darned complicated in the motivations and actions of the key players, and dumbing it down gives lessons which are near, fit very nicely into modern tropes and are also almost entirely wrong in the messages they convey.
Then you've got questions like "was Cromwell unusually enlightened on issues of religious freedom or a religious extremist with a vicious hatred of anything that vaguely resembled Catholicism?" to which the correct answer is "both actually, and simultaneously". And the likelihood the whole thing could have been avoided if a king who wasn't exactly unusual in his behaviour for contemporary monarchs was actually good at politics or military planning, and that having taking the unprecedented step of executing a monarch for refusing to acknowledge them, Parliament then let a gentleman of modest background and means rule whilst refusing to acknowledge them them because he actually was good at politics and military planning.
Then there was the Glorious Revolution which wasn't actually a revolution a couple of decades and two kings later which was way more influential on democracy and religion in modern Britain and gets studied way less...
As every British schoolboy knows, there is only one narrative....
Royalists: Wrong but Wromantic
Parliament: Right but Repulsive