You're No John Updike!
Comparing your career with that of some well-known, accomplished writer is a waste of time, not only because it adds to the shameful self-recrimination most struggling writer already endure, but because it misses the point.
The reality is, every writer can't be a Robert Towne, or John Updike or Preston Stuges or Ernest Hemmingway or Jane Austen. For one thing those writer beat you to it. They're them. That job is filled.
More important, they're not writers you're really in competition with. No matter how successful you are, no mater your level of talent, your true competition is yourself.
Think of it this way. Maybe every writer can't be Proust, but every writer can be a better writer. Comparing yourself to others not only deflates and devalues your own efforts, but actually mitigates against the very thing that has the potential to improve your writing--the private connection to your inner world of experience, that wellspring of authentic feeling and desiref rom which the impulse to write arises.
When I say that your true competition is yourself, I'm referring to your willingness to engage daily with what's going on inside you, your courage to dig deeper, your passion to now what it is you really think and feel and to find creative expression for it.
Maybe you're no John Updike. But when you're writing from a place of excitement and authentic feeling, who needs to be?