I was comparing with a cold not with influenza.

We could try to make the comparison you are suggesting instead. But to make a valid comparison we need to consider:

Is influenza infectious for 10 days before any symptoms show?

How many people get the influenza vaccine each year? I.e. is there some herd immunity built up?

The symptoms of influenza are universally nasty for everyone infected. No one with the flu is walking around and going to work (if you think do then you don't have the influenza virus you have a cold). It seems that at least some people with this new corona virus just have cold like symptoms and therefore will not by default be self-isolating like people with influenza naturally do.