Yep, totally agree. But look at what Trump did here in the US, with calling the press "the enemy of the people" and saying journalists should be jailed. He took it the next step which was advocating violence against the free press. Look at Putin now, jailing anyone for 15 years if they call this Ukraine war anything but a de-Nazification exercise.
I was in Russia for the World Cup, and as much as I loved my time there, I was well aware that I was in a country where talking shit about the ruler could get me in serious trouble. It's something we take for granted here in the US [I don't know where you're from Sir Donkey of Fish], that we have free speech. It's the right that lets us tell Trump to eat a bag of dicks. It's the right that holds politicians to account. It's the right that shines light into the darkness etc. etc. (cue dramatic music). This 19 year old was an idiot. He did some racist things. Anyone think going to prison is going to lessen anyone's racist beliefs? If anything, he'll find fellow travelers. But again, US prisons are an atrocity, maybe they are a lot nicer in the UK.
There are lots of limits on free speech, it's not absolute. I would be very afraid if someone like Trump were able to get a law like that one passed here.