The virus is dangerous, albeit not in the way that most people think.
Our institutions, like health care and education, have been running so close to the edge for so long that the added pressure is pushing them over the edge. Before the pandemic, teachers would show up to work sick since they knew there may not be a substitute to take their place (and certainly not a substitute who would ensure continuity in teaching). Before the pandemic, nurses would work marathon shifts since there was a staffing shortage even before taking sick days into consideration.
Now we are in a situation where we have to slow the spread of the virus to protect our institutions. I cannot speak to whether the measures are genuinely effective or a manifestation of security theatre, since that is not my domain. What I can say is it is putting more pressure on the limited amount of staff available. This is more than missing work because of a close contact. It is because of people missing work because they are genuinely sick or people being unable to keep up with the added responsibilities (such as teaching when they are supposed to be prepping).
Unfortunately, we cannot solve the resource shortage overnight. Even if we could magically train the people to fill the role overnight, we don't have the infrastructure to support them. So now we are paying the price.