He lost because like every politician he was trying to compromise in order to get elected, and he couldn't compromise enough to win over the racist public of his time. I don't see any reason to believe that he was completely comfortable with any of those statements. As bad as these positions sound now, The fact that he was personally opposed to slavery made him too extreme to get elected, even though he argued that the evils of slavery were constitutional. (Which is why he eventually abolished it with a constitutional amendment.)

I'm grateful for this article. I have heard fragments of many of these statements before, and it's good to have them collected in a single spot. It's important to know that Lincoln was a man of his time, and that even the best people of his time were morally deficient by modern standards. But that doesn't mean we should judge him by modern standards. His differences from us are part of what enabled him to achieve what he achieved. He would have no chance at all of getting elected if he had demanded votes for women, or that everyone should specify their pronouns before beginning the debates.

I develop these ideas at greater length here.

https://teedrockwell.medium.com/save-our-imperfect-moral-heroes-e490dced158c