UK is its own kind of dump, and has the same anti-immigrant dumpster fire being stoked by the media to distract the populace while the politicians & their friends finish looting what little is left of the country. Would not recommend.
The UK is much more run down and low-quality than the rest of Europe.
EU gives you a choice of price & quality - you can pick what fits your budget best. You can have dirt-cheap but also run down/shitty, or you can have expensive (but still nowhere near the UK) and pleasant.
The UK is the worst of both worlds where it's both expensive and shitty.
I have lived in Germany for 5 years but am from the UK and I don't see much difference overall. The UK is just a bit more individualistic, much less racist, and has London, which has the highest wages in Europe. Germany has less income equality but far worse wealth inequality—most people in Germany will never own their own home because although Germany is rich, Germans are poor. Healthcare is better here, though. It's just a case of picking your poison I think. Also, believe it or not, Germany has its shithole cities too, I've visited a few of them.
But of course the received wisdom is that the UK is a third world shithole with more in common with the Democratic Republic of Congo than any European country, so as you were.
It has the same problems of having an ageing population as the rest of Europe. Brexit is bad but relatively small in comparison to the demographic challenges. I live in Germany and it's in a sorry state too, because there are so many old people.
i know europe is making it easier for grants/proposals to go through and lessening the overall time it takes for grants to be accepted, for people in academia leaving the US