An October 2019 novel Coronavirus simulation by Johns Hopkins Center for Health Security, World Economic Forum, and Bill & Melinda Gates Foundation [1][2], projected 65 million dead and widespread knock-on economic and societal problems during 18 months of pandemic. Not that this is a likely outcome for nCoV-2019 (which is likely less lethal than the imaginary virus), but it's worth understanding SARS-like viruses can be significantly more serious than the flu.
Secondly, the flu is "baked in the cake" in our general medical and societal infrastructure. A novel virus will be additive to flu infections and even at similar rates of infection/death could cause a noticeable impact. As an analogy, 1.25 million people die in road crashes each year, but if some catastrophic, widespread automotive software bug/malware caused an additional 1.25 million road deaths in 2020, it would rightfully be a massive story, could potentially overwhelm emergency and medical services, and would be something to be concerned about mitigating as much as possible.
[1] http://www.centerforhealthsecurity.org/event201/scenario.htm... [2] https://youtu.be/AoLw-Q8X174