Just completed season 1 of LoK. For context Amon father was a bloodbender who can bloodbend even on day but his bloodbending got taken away by Aang. Amon and his brother still become a bloodbender.
I thought the twist of Amon being a bender really undercuts that seasons story arc. The Equalists were asking a questions that makes sense in their world, benders are ridiculously more powerful than non-benders and in their world's history (at least in Aang's time) held almost all significant offices. The equalists had a fair question about how to even the play fielding for all citizens. But this question isnt answered or considered, Amon comes out at as a bender and the equalist movement is forgotten about