Gerry didn't invent gerrymandering. The practice predates his example, and he wasn't even the one who made it happen in his famous example. He merely signed the bill enacted by the legislature. All he did was happen to be associated with a prominent example that got a name that stuck.

It's not really something that can even be invented. Once you have elections in districts with boundaries that can be altered, it follows straightforwardly that people will try to alter those boundaries in ways that benefit them electorally.