Therefore it works for everyone.
There are lots of people that do not make friends easily. There are lots of people that do not have friends in the industry that they work in. There are lots of people that have moved very far away from any friends once or many times in the past few years and have either completely lost contact or don't have friends that would be in any position to throw other contacts your way.
So no, it is not just go make friends and everything will be great.