Well, Cromwell the issue was that it was an extremist fascist coup by a religious extremist

He literally banned parties, and advocated that instead everyone must go to church and make good with god

I mean, after doing a genocide Cromwell declared his son his political heir... I don't disagree but it just never had a chance because British people barely knew what a republic was. They literally just had classical-inspired vibes about it.

No joke, I wrote a paper in college that sourced an Enlightenment era English writer who claimed that the English state was a monarchal republic because the citizens had more rights than the French.