It's easy to get comfortable when you stick to the same thing.
This isn't always bad. Comfort offers stability, or at least the impression of it while times are good, and it helps develop focused expertise. With the right focus, you learn to do specific types of work to a high standard and have the opportunity to get really good at them.
But this limits your opportunities for growth. Rejecting chances to try new things because you don't think you're capable leads to a life that's reliant on everything staying the same.
Step outside of your comfort zone to see what else you can do. Take the opportunity to make mistakes and learn from them. Protect yourself against changing demands and develop the skills and knowledge you need to meet them.
I'm often guilty of overthinking and worrying about hypothetical things. This has been a pattern throughout my life, and it can be especially crippling as a freelancer. I've learned that falling into these thinking patterns and seeking comfort holds me back from doing my best work and reaching my full potential.
Good things happen when you're brave enough to go after them. Embrace the ride, the rewards are there if you dare to seek them.