yes wifi is very unsafe, because if you are around hackers all the data that is in your pc surely sold in the grab the hackers.
so do not use wifi use your own personal data, little capital for your own security.
yes that's when we use public wifi, because public wifi is used by anyone, sometimes people who have a specific purpose can also use public wifi.
then we in using public wifi must also be careful that the data we have it will be safe from anyone who intends evil.