As I understand it, and I'm not a doctor or an expert in how diseases spread, the issue with coronavirus is the combination of the fact that it is thought to be more contagious than other viruses such as the flu, plus the fact that it has a higher mortality rate. The mortality rate is still relatively low - the vast majority of people will survive the virus - but because it is a lot easier to catch, the number of deaths from coronavirus will be higher than the number of deaths from SARS even if only a relatively low proportion of people who get it die of it. So that's why it is important to try to contain it.
Also, we don't have a vaccine for it, whereas we do have a vaccine that can be offered to immune-suppressed and vulnerable people for the flu that makes the rounds every year.
So I don't think that the fact that governments are trying to contain this is at odds with the risk that it presents, particularly.