I spent a couple of hours trying to research the anti vote. CNN exit polls answered 2020, 24% anti vote, 2016, 25% anti vote. Gallup answered 2012 with 11% anti voters. Then I hit a dead wall as none of the previous exit polls asked that question. I would assume 11% give or take is/was basically the norm going back. But you know what they say about assumptions.
I think common sense left the political arena in the 1990's or early 2000's. Lott and Daschle were replaced by McConnell and Reid which I classify as party firsters, where each would automatically oppose anything from the other party. I think the impeachment of Bill Clinton and the introduction of the Hastert rule was the beginning of the lack of common sense. Others may see things differently, but it was with the take over of the two parties by McConnell and Reid that cooperation between them stopped, straight party line voting began in earnest. But this is just me.
I think Biden, Manchin, etc are trying to bring back cooperation and common sense, but I don't think they'll be successful as long as McConnell remains.