Yes the American media overblow some of the issues for clicks. However you can be arrested for speech and it isn't just threats to violence.
> In the US, you have people being literally grabbed off the street and sent to foreign prisons because of their speech with no due process.
This isn't true. Many of these people were arrested because they had entered the country illegally and then sent to foreign prisons. You are falling for the same rage bait media (except it is left leaning).
> This isn't new, of course, I remember some time back I was being told how white people couldn't go into Leicester... while I, a white man, attended University in Leicester.
It depends which area of the city. The University will typically safer than other areas of a city. Most of the people there are students and there is campus security.
There are areas of Manchester (where I used to live) and where I am the only English guy (not white, there were Irish people there) on the street. There was significant racial tensions and fights as a result. The guy that bombed the Arianne Grande concert lived a 5 minute walk away. I moved out of Manchester because I didn't feel safe.
Again not a "no-go zone area", but there are problems with racial tensions. I've heard it is worse in some places in London.
> The UK definitely has issues, even ones related to expression, but generally it's a very free place that does pretty well with respect to it.
As someone that lived outside the UK for long periods of time and knew what the country was like before the 2000s. This isn't true.