Interesting bit of analysis Tim, though I think it bodes well to continue to be cautious.

Firstly because the virus is replicating in an exponential manner, so even if it is genuinely less virulent the exponential growth in numbers of cases will easily outstrip the % reduction benefit of seriousness, and the total number of serious cases will increase to the point that hospitals could be swamped.

Secondly because a narrative that Omicron is less virulent suits the UK government, which has consistently tried to ignore the virus and carry on with business as usual, being driven by "the economy" and a desire to achieve "herd immunity" regardless of cost (resulting in the past in both high death rates and more economic damage). So forgive me if I take their pronouncements, based on a relatively small number of cases (compared to the millions analysed for earlier VOC) and issued just before the sensitive Christmas spending rush, with a pinch of salt.

Thirdly, there is no evolutionary pressure on the Coronavirus to become less virulent. Something like MERS or Ebola which kill 70-80% of victims would benefit from becoming less lethal, since anything that kills its host population creates an evolutionary dead end. The SARS CoV-19 virus however only kills on average 1% of those it infects, so there is no need for it to become less virulent. Its strongest weapon is its infectiousness, and the R0 of the Omicron variant seems to be 4 or 5 which is incredibly infectious. While I am no virologist it seems to me that a virus that enter cells so easily is likely to increase viral loads in victims and become more, not less, virulent. I'm happy to be proved wrong on this.

And finally fourthly, the host population has to be considered when comparing virulence with earlier variants. There are a lot more vaccinated folk about now (in the UK anyway - though there are many poor countries with barely a few % done) and it is likely those who are catching Omicron now are either younger unvaccinated folk or older fully-jabbed-up ones, both of which are less likely to experience severe symptoms.

Maybe there's light at the end of tunnel but I think it'll be at least another year before we know if it's an oncoming train or not.