As the other commenters have noted, there are a lot of great examples of how creative folks use constraints to enhance rather than hinder creativity. The mainly French writing group Oulipo takes this writing with constraints thing to outlandish extremes. A famous example is George Perec’s A Void, a 300 page novel that’s written entirely without the letter E. You can look them up on the wikipedia for more info of course, but I would like to point out one quote:

The group defines the term ‘littérature potentielle’ as (rough translation): “the seeking of new structures and patterns which may be used by writers in any way they enjoy”.

What I love about this is the idea of constraints as enjoyable tools.