A developer is anyone who can use the available tools to transform something into another tool to reach a goal. A developer may do these things individually or pay others. A developer doesn't need to have skills if the developer has the resources to obtain others with the needed skills. A developer might also work for other developers in developing these tools in exchange for money.

So, yes, I think anyone can be a developer. The bar for becoming a developer isn't much higher than being able to open a web browser and perhaps search Google. For example, if you want to create an e-commerce site then there are lots of hosted services which will set one up for little to no cost.

At the end of the day, you are either reaching your goals or you aren't. Compare an grandmother who can barely figure out the internet but makes a healthy income off selling items online (perhaps things she has made which and have gained a following) and a ninja engineer who has been mired in feature creep for three years and still isn't close to getting his start-up off the ground (and probably never will)