Yes the UK does more testing, but the UK also has a lot of covid. Check the deaths per million population in the last seven days because deaths are independent of how much testing is being done:
https://www.worldometers.info/coronavirus/weekly-trends/#weekly_table
In Western Europe the UK is highest at 14 per million, closely followed by Ireland at 13 and Isle of Man at 12. The next closest Western European countries are Belgium and Austria at 9.
I still think the most revealing thing is to look at variation over time. I just opened the Worldometer daily cases curves for a load of European countries. We should all by now be familiar with the shapes of covid waves; compare a country’s current figures against its earlier peaks. France, Spain and Sweden are in troughs. Belgium, Denmark and probably Italy are just on the rise. Germany and Austria have been rising for a while and are quite high.
The UK has abandoned all social restrictions and positively encourages infection with its schools policy. Around my way hardly anyone’s even taking precautions any more. What would be the point? It’ll get to you through the school kids anyway. Protection from our early vaccinations is also wearing off, so the UK’s on a high and rising plateau.