Earlier quoted context omitted.
Can you offer an example of someone being jailed for "disagreeing with the extreme left on social media," or is this an alternative fact that you've acquired via osmosis? I am aware of people being jailed in the UK for making terrorist threats on social media, and arguably those prosecutions were inappropriate, but that doesn't appear to be what you're claiming.
All you have to do is search for it yourself. It’s not just UK citizens that are affected. They’re threatening to have US citizens extradited to the UK to face charges [1] for online speech that’s protected by the first amendment. [1] https://thenationaldesk.com/news/americas-news-now/uk-author...
Similarly, the links again show that you are whitewashing the events: those people jailed weren’t “disagreeing with the extreme left” (every leftist would be in jail since they disagree with each other constantly) but for things like saying they were going to a violent protest and advocating burning down hotels where refugees were living. Going to a highly plausible specific threat is quite far beyond disagreement.