From The Centre for Evidence-Based Medicine at Oxford Uni...
https://www.cebm.net/covid-19/the-innacuracoes-in-the-sage-models/
'Over-estimation' 'out of date models'
It's double speak and reeks of deliberate misleading, I'm afraid.
That's your interpretation of their words, which don't ever say "deliberate misleading".
They do criticise out of date models and prefer the MRC method of continuous updating. But all the models are continuously updated. You can't wish for updates then also complain when they are revised.
Some other things I find odd:
1. they use the graph shown by the CMO about potential deaths in the UK using various models. You and others have consistently referred only to the highest of the four groups' estimates they showed - which, as you say, was almost immediately downgraded. I think the purpose of presenting that graph was that we were already in advance of the 'reasonable worst case scenario' envisaged way back in August. Times move on, and that was clearly an inaccurate projection. The second wave came far sooner than expected, likely due to the early relaxation of restrictions.
2. they use the graph shown by the CMO about potential deaths
in the UK using various models, then compare those dismal projections with the reality of deaths within
England. That switch is very badly signposted in that blog. Honestly, did you notice it?
3. they use the graph shown by the CMO about the potential toll in the event that there were no further restrictions. It might have been sexed up, or whatever, by presenting the worst of the potential outcomes. As you have shown, it is difficult to persuade a nation to take action before they see the deaths rising. Unfortunately those deaths are baked in before we get to see them. Here we are after 3 weeks of lockdown (and the threat of that beforehand, which has an effect on behaviour too) and numbers seem to be peaking at 'just' ~500 a day. Since, at that point, infections were doubling every two weeks or so (is that right? I can't quite remember), if we had carried on as we were then, there is just cause to believe we could be up at 1000 in a couple of weeks from now. Unless you believe in the unicorn magic of the virus having already just "running it's course" or "fizzling our naturally", etc.
Even if it has now peaked, 500 deaths a day in the UK for a while is not much cause for celebration.
Once again, the economic impact / livelihoods / etc issues are a different story.