It will be interesting to see the final numbers and how this plays out for the next year, I remember being told by creditable scientists that CJD was going to kill a million people in the UK.
You are absolutely right, the only way to minimise the death rate is for everyone to stay indoors until they rollout a vaccine (just staying indoors for a year without a vaccine is just delaying the invevitable), that is not going to happen, so we are then in the realms of what level of deaths is worth it versus the economic impact. I would guess we are going to be in and out of isolation of various restrictions for another 6 months until we get herd immunity - around 38 million people. Like I say, keeping people inside for 12 months doesn't seem practical to me.
The current death rate is normal flu is ~0.1%. The current death rate with COVID 19 is ~4.99%. COVID is very nearly 50 times more deadly than flu.
no one knows the death rate because they are not counting everyone with it. Until the rollout an anti-body test and can test millions of people to see who has had it, its all guess work.