ONS data apparently confirms that current death rates in the UK are about normal for this time of year.
This Telegraph article makes the point that people are probably dying from Covid-19 who would otherwise die from flu. This idea is confirmed by the fact that flu deaths are, according to ONS data, less than usual compared to the 5 year average.  ” influenza and pneumonia deaths were below the five-year average (2015 to 2019) in every month.” [data range: January 20 – 31 August 20]
The key point is this:
Covid-19 plus influenza/pneumonia deaths are at 1,621 this week, while five-year average flu and pneumonia for this week is 1,600
Taking into account an expected year on year increase due to an increasingly aging population there is no (that is zero) higher rate of deaths this week than compared to the 5 year average. Without taking account of this factor there have been 21 more deaths.
It seems completely possible that the entirely incompenent senior health civil servants are just looking at the Covid graphs and have failed to understand this basic point.
If the answer to this is the answer given after they were found out faking the data that “anyway hospitals are still full” – again we have to turn to the fact that hospitals are currently experiencing a normal level of Intensive Care demand. 
It is true that Covid-19 is more infectious than flu and it is possible that over the next few weeks there would have been a surge in demand for hospital treatment which would have put the system under strain. Though against this is the fact that there is some evidence that the local lockdowns were already having an effect and the r number was falling. 
Im summary – it seems that that this lockdown, with its devastating impact not only on economic and social life, but also in terms of deaths as people with conditions such as cancer, heart disease and strokes do not receive the treatment they would normally, may be entirely unnecessary.
If it is necessary it is to avoid a situation where hospitals come under pressure to treat people and have difficulties absorbing them into the normal bed system leading to the sight of makeshift arrangements such as a few cases of patients being treated on stretchers in corridors. It is almost certain that this – the need to avoid TV pictures of a small number of patients being treated in makeshift conditions in the NHS – is the sole reason for the present lockdown. This happens because the NHS is a kind of national fetish. No politician who is thinking about their political skin (and this lot certainly are) can afford to allow any images of this kind on TV on their watch. This is why the Department of Health and Social Care killed 16,000 elderly people by pushing Covid infected people out of hospitals and into Care Homes in February, March and April. (An act which Amnesty International called a “scandal of monumental proportions” but which in this debased day and age has passed virtually without public comment). Mass casualties in Care Homes don’t resonate with the public in the same way that overflowing wards in the NHS do. This situation also highlights the fact that the NHS has very little spare capacity. Even a bad flu year can put it under strain.
Again – on very best interpretation the rationale for the current lockdown is to prevent a few hospitals going over capacity and having to treat patients in makeshift arrangements. The exigencies driving the current lockdown are PR ones not medical or ‘scientific’.
- https://www.telegraph.co.uk/news/2020/10/20/dont-believe-scare-stories-hospitals-running-icu-beds/ https://www.telegraph.co.uk/news/2020/11/03/hospital-intensive-care-no-busier-normal-leaked-documents-show/