Of course, for people in the UK it is uncomfortable to be labelled "bad", never mind "the worst" - but before dismissing the statements out of hand, denying and/or in some way trotting out excuses for the outcome, accusing others of doctoring their results, etc., etc. in fact anything but accept that it may well be true, let's just check a few facts out.
The data are all here
https://www.worldometers.info/coronavirus/
and do what we might, only by one measure on this listing is the UK not quite the worst in Europe: Belgium has a higher figure for deaths per million of the population. On everything else the UK has the worst figures.
Add to this an aspect not listed there (one that to me is particularly relevant and telling) and again the UK comes out badly: In the UK just under 14% of all cases resulted in death - getting the disease is really only seriously bad news if you die from it. Recovery means continuing where you left off, happy days again. France is worst with over 18% as a death rate (Belgium over 15%, Italy 14%) but that is little consolation when you consider that one European country has achieved a just over 0.5% death rate and others also far, far better than the UK. If the UK were the best then (proportionately at 0.5%) 42,000 people here would still be alive as opposed to dead. This is nothing to be proud of, to clap for or in any way to see but as an awful tragedy. This has nothing to do with population density, type of accommodation or any such thing - it is the failure of the health system to keep sick people alive. The only reason people have died at a higher rate in the UK than elsewhere is because they were not saved while people elsewhere also ill of Covid 19 were saved. British people are no more naturally doomed to die than foreigners, at least when one assumes they receive the same level/quality of medical care.
Suggestions that figures issued by other countries are less reliable than the British ones are not worth taking seriously, there has been enough confusion over the UK set already. Also, to say that the UK was worse placed for being an island would be nonsense, silly to suggest that it was handicapped because it has strong, long established universities and research establishments plus industry capable of producing everything needed to deal with the pandemic. Nobody would seriously suggest the UK lacks qualified personnel to turn to or bodies to mobilise in general or that distances to health care facilities are too great. No, the UK should have been able at least to be mediocre at this.
The European country which did so well (0.5% death rate) is also an island, has very few resources relevant to dealing with the crisis, must import everything for dealing with the pandemic and only has a small number of well qualified personnel to call on. Yet, after a steep initial rise, they eliminated the curve in nine weeks (no flattening, just sharply up and sharply down). The key is that they were prepared, are well organised, focussed and united when applying effective measures.
No, there is no escaping it, the UK now really should take a long hard look in the mirror and question whether it still qualifies for its favourite self-congratulatory, self-awarded label: First Class, World's Best, World Beating, etc. Admitting reality would not be anti-British, denying it would amount to continuing to do gross anti-British harm to British hopes of improving and crawling up from being at the bottom of the class. I know of people abroad watching the UK being their own worst enemy with a mixture of astonishment and sadness (yes, some ridicule) - they would in fact be pleased, impressed even, to see the UK do something rather than pretend they don't need to and it was all inevitable and as good as could have been hoped for.