I couldn’t tell you what episode literally anything is from, ever. Not how my brain works. I don’t know the title or number of literally any episode of anything I’ve ever watched, even my very favorite things.
OK. That
is how my brain works, and I don't recall Bendu being proven wrong in any way, shape or form. Unless you meant his philosophy has been proven wrong in some other part of the Star Wars media and not directly on the show?
I think what it boils down to is this: in the past, George Lucas said that the dark side was like a cancer and that "balance" meant eliminating it all together. However, the EU brought in the dualistic idea of balance meaning equal light and dark sides, and Disney seems to have gone with that interpretation. But there were elements of the latter interpretation in
Clone Wars even before George sold out -- see the "Mortis" trilogy of episodes from season 3 of
Clone Wars, which were referenced in one of the last episodes of
Rebels.
To save you hunting, this story involves three powerful "Force wielders": the Daughter, who represents the "light side"; the Son, who represents the "dark side"; and the Father, who maintains the balance between the two.
Incidentally, Ahsoka dies in the Mortis trilogy and is brought back to life by the Daughter, who sacrifices her life. That's why Ahsoka has that little owl creature that follows her around. Some people are even theorizing that Ahsoka
is the Daughter -- or at least has taken her place as the "goddess" of the light side of the Force.
Bendu in
Rebels also refers to the light side as "ashla", which Ahsoka uses as her alias while hiding from the new Empire in her eponymous novel. "Ashla" and "bogan" (for the dark side) were also the original terms Lucas came up with for the two sides of the Force.
To be perfectly honest, I'm not sure Lucas ever really made up his mind about what bringing balance to the Force actually meant. He seems to have changed his own interpretation over the years.