Are you daft? The part bolded by me above is a boldfaced lie. That is the grossest distortion of the Corwin Amendment that I have ever read. It indicates a disturbed mind. Read again the President Lincoln quote that you provided, "the Federal Government shall never interfere with the domestic institutions of the States, including that of persons held to service." In no way does that mean slavery was irrevocable. It means the Feds could have no hand in interfering with it. It meant that Lincoln had no power to interfere with Southern Slavery. It gave the States sole power to deal with slavery, each within its own borders. This was an effort, and a good one, to forestall the impending Civil War. In fact Lincoln personally sent letters to each States governor to be sure they knew of the amendment. The South would have none of it. When will it occur to you that the South had ulterior motives in seceding? Perhaps having to do with their own political and economic (peculiar) interests? Most lost causers say slavery would have ended soon anyway. What was the problem that the South had with the Corwin Amendment?
Critic answers Lincoln.
Lincoln used the word “irrevocable” in his first inaugural address. Below I re-post Lincoln's comment so you can read it for yourself.
“I understand a proposed amendment to the Constitution — which amendment, however, I have not seen — has passed Congress, to the effect that the Federal Government shall never interfere with the domestic institutions of the States, including that of persons held to service. To avoid misconstruction of what I have said, I depart from my purpose not to speak of particular amendments so far as to say that, holding such a provision to now be implied constitutional law, I have no objection to its being made express and irrevocable.”