I used to use Drupal in my everyday work. I got very familiar with it, how it worked, and how to avoid its (many) pitfalls. I was able to build sites that met client needs quickly, and they were able to make use of them.
Then I decided to change jobs, and I consciously turned away from being a “Drupal guy”.
The thing is, when you are really experienced at using a particular piece of technology, the prospect of moving on from it can be intimidating.