On one hand, the idea of being more creative with limited choices makes sense. You have to try harder to make things work, which helps you come up with more original ideas.
On the other, no successful creative person ever truly believes this. What successful guitarist doesn't own a ton of guitars. What successful film composer purposefully limits the instruments in his orchestra? What successful writer purposefully limits their vocabulary? And on and on and on.
(The only exception, generally, to the above is some sort of stylistic choice)