Seems to me that there are two types of fear whic could be at play, both quite different.
There's the fear of some life-threatening event, but I suspect the more common fear for new pilots is the fear of simply not being as good as you want to be. It's a big mental investment in learning to fly and most people want to do it well. On the one hand, you have a PPL. On the other hand, mosty of us realise then just how much we really have to learn.