early data are based largely on reports from South Africa—a country with a relatively young population and high level of prior infection—and on reports involving international travelers, who tend to be younger and healthier.
If Omicron does cause less severe disease than previous variants, the sheer number of infections could still result in a similar or greater number of severe cases.
In Denmark they are doing a limited lockdown. Children were sent home from school a week earlier than planned, cultural institutions were closed down and they made it mandatory to have a valid "covid passport" on public transit.
Restaurants and bars are still open though, although with limited hours.