That's an interesting line, most developers became so because they grew up with computers, tinkered and understood and then built small, then bigger things. Likely hood, most developers are what they are because they couldn't do anything else.
As a business owner, I'd be wary and want to see what you actually built by yourself.
Your approach might work best augmenting your current position. In small/medium companies, wearing different hats is indeed useful, so if I were you, I'd have a small portfolio of completed personal projects and I'd sell myself as a product guy and a developer.
Either way, supplementing your personal and professional pathways should most likely never be something to regret. It's a good thing to diversify.
My concern is about your instant jump into "fullstack" developer. It's not easy to be a good front-end or back-end developer, nowadays everyone is full stack... but they really only know one or two dynamic languages. I'd prefer you said either back-end or front-end. Not many developers I've met are really fullstack, they're mostly full of it.
