No, the assessment is realistic. The conference is in about one month. If the coronavirus is transmitted there, which is not unlikely, then it can take several weeks until someone gets symptoms, then another month until that person is no longer a transmitter. Not showing up to events during such a long time is unfortunately not a good idea for someone who doesn't have tenure. Maybe this changes once the official evaluation of the situation has changed. Right now it is "There are no cases in Portugal". Our university hasn't even provided hand sanitizers yet, and there is no official or inofficial statement from the administration about Covid-19.
I meant what you said about the 3 months could be a suicide for your carrear.
About the rest, I'm from Portugal and I agree - I believe there are cases in Portugal for some time and probably will be confirmed the first ones next week.
Within a month the currently hidden outbreaks will have become visible and we'll probably have measures similar to what Italy and South Korea are doing now in the whole of Europe.