It's important to note that this depends on all nation's figures being directly comparable, which is not really true. Until we have a proper picture, which may be months from now, there's no certainty about whether more people have died from/because of Covid-19 in the UK or in, say, Spain/Italy.
That doesn't necessarily mean that the question isn't worth asking. At the end of February/early March the story was how we were "three weeks" behind Italy in terms of the outbreak progression, and it's right to ask whether or not the Government made the best use of those three weeks. But a true answer about what went wrong will have to wait for the public enquiry that really must be held at some point.