There's no more to it than that, the other definitions you see are how the term got bastardized over the years. The reason you see "based" in online conversations all of the time now is because many started using it immediately after the Fappening.
Based occurs and is said when someone cancels out their own argument or another persons argument, typically using their own words or talking points against them or when someone proves that they agree with what they’re trying to contradict. Can also be used for someone who cancels out an action that results in an unintended consequence.
Ex If someone says air pollution is horrible, and then you say well stop driving your car, that’s based.