I know that now, having seen the pilot. But I still think it's kind of lame. People are way too scared of magic. I happen to find it fun, especially in superhero settings where it can clash with technology and other sources of powers.
I have a few theories as to why this might be:
One, it is hard to do right. Introducing magical elements would require the creator to think out carefully the rules that regulate such elements. A lot of thought needs to be put into it as creates the framework for the world in which one's stories take place and having said elements portrayed inconsistently would result in a loss of suspension of disbelief. Handwaving a singular fantastic element the way The Cape did is much less complicated and carries fewer repercussions for the story.
Alternatively, they don't want to hedge their bets. Creating a setting as close to 'real life' as possible means the creators leave open the possibility of going down magical, sci-fi, biblical, etc themes at some point down the road. Choosing one right off the bat effectively prevents them from going down those other avenues instead. Sure, you could argue that comics are able to feature all of these elements within one title. However, those that do have had a much longer period of time to introduce them and more importantly, similar titles have established such a practice. Television series, not so much.
On a more meta approach, the reason we don't see magic-using superheroes is probably the same reason why we don't see sci-fi superheroes, Wild West comedies, etc. The more one subcategorizes a show, the smaller the niche audience will be. Hence, a simple, more 'realistic' superhero series would have, in theory, a broader appeal than a show about a magic-using superhero.
Heck I'd watch a series just about her and Micah. Heroes wasted good characters and focused on the inconsistent and annoying ones. The Cape has the potential to be so much better if done right.
