Creativity is not magic. It's an acquired skill. It flows easily with practise. Yes, there may be people who are naturally more creative than others. But this is no different to someone excelling at maths or science. I personally gravitated to music, and I believe this is because my natural way of thinking lends itself to it. I am probably an aural learner, and while I was never strong with maths, the equations that exist in music somehow made better sense to me.
I've never doubted my ability to continue to create, and therefore have never placed unwarranted value on anything I've done. Much like a writer who willingly deletes a whole chapter of their new book because it just wasn't working.
I sometimes work with people who have created a piece of music and have come to believe it to be like a rare gem, that they will never be inspired again. These clients can be harder to work with because they will coddle the work and stifle it in order to protect it. From a producer's perspective, it is likely the piece could need tweaking and convincing these kinds of clients to trust me with their work is always tricky.
In reality, the well of creativity in us is bottomless. My profession means I need to be creative at any given moment, and not have to wait until inspiration strikes, and generally speaking I can do it. On those rare occasions I can't come up with something, it is usually for other reasons, like fatigue, low mood or distraction. I don't attribute it to a mystical force failing me.
So for those of you out there that don't think they have the 'creative gene', I assure you that you do. We all do, and by simply doing it regularly you'll find that not only can you do it more often, your creations will get better and better.