Denmark and South Africa

There are half a dozen factors that influence the impact of the virus. Average age, population compliance, existence of regionally-specifc corona viruses, robustness of the healthcare system, general health of the population, etc. Let's wait and see what it does to the healthcare system in Canada before we assume much.

it does literally nothing here except possibly reduce severity to those who have extreme co-morbidities

Unvaccinated people show up in hospitals and ICUs in Canada in vastly larger numbers, proportionally, than vaccinated people. It would be nice if Omicron changed that for the better, but the speed of its transmission is a new factor and it remains unclear whether there will still be too many for the healthcare system.

I'll look at the tweets later and respond separately.

95.58% of Omicron cases

Case counts aren't as valid anymore - the counting system is overwhelmed. It's hospital/ICU counts that are the best indicators now.

your protection goes negative

The protection against infection wanes significantly. The protection against severe illness remains fairly strong. It's New Years and I have to go pretty quick but you can look it up. Boosters do help, of course, so getting one (or however many we're going to need) improves your chances of staying out of the hospital - and not passing it on.