You asked what the dips represented,
@j4yj4m gave a response. There's a cycle to Patreon where people stop supporting on the first. The point is that even if you don't donate, you still get to play the game. You might not have access to other features such as voting but you don't really need it when there's other ways to communicate.
From the outside looking in, you asked a question, you got an answer, you moved the goalposts. Even with the historical argument, the point was valid. People stop pledges when they no longer feel the value is worth it. Whether that's for polls or not is their individual self interest. Not the point being made.