D&D wasn't even the first IIRC. There were other role-playing games at the time, including fantasy RPGs. D&D was among the first fantasy RPGs to have a commercial release. A lot of games were unique to each DM, running their own homebrews.

Then there's all the wargames and detective/mystery games RPGs grew out of that existed for decades (in some cases centuries) before D&D.

But yeah. It's like the worst system. The more I hear about it and its history, the more I want to continue never playing it.