I’ve published (some 5 years ago) this line that echoes your sentiment:
Fear of success stems from a greater self
mistrust than fear of failure.
With fear of failure, some of it is about what will others think, whereas most of fear of success has to do with ourselves.
By random association I think of endurance artist, David Blane, who through his fears dares to remind us of our greatness (as you do, here).
One of his feats of endurance involved starving himself in solitary confinement, suspended from a crane by the River Thames in a glass box for 44 days. The illusionist believed that living without food and human contact, he’d experience “a higher spiritual state,” that would lead to “the purest state you can be in.”
Members of the public repaid him for his efforts by pelting him with insults, paint-filled balloons, tomatoes, golf balls and other forms of violent distraction; i.e. trying to cut off his water supply, and flying a remote controlled helicopter carrying a burger up to his box.
This is the mob’s unfortunate suspicion, nay, outright hostility towards the exceptional. As you surmise, people are loath to be reminded of their own neglected human possibilities...