The Lincoln-Marx connection is rather overstated. Marx sent letters, Lincoln likely did not. There is often an attempt to rehabilitate Lincoln that I understand from a certain angle, it would be nice if they were not all absolute bastards and it would mean there is a unique, historically progressive force within Amerika somwhere that we can celebrate. Unfortunately, Lincoln is not worth rehabilitating, either. He was notably unkind to natives (as in, perpetuating violence unto them which he would not even grant confederates, because he was a racist settler https://www.thenation.com/article/archive/largest-mass-execution-us-history-150-years-ago-today/). His actions in office while commendable, stemmed only from pragmatism and a desire to maintain national cohesion (“preserve the union” 🤮) and Lincoln personally detested black Amerikans, from a speech given in 1858 for his U.S. Illinois senate bid:

I will say then, that I am not nor ever have been in favor of making voters of the negroes, or jurors, or qualifying them to hold office, of having them to marry with white people. I will say in addition, that there is a physical difference between the white and black races, which I suppose, will forever forbid the two races living together upon terms of social and political equality, and inasmuch, as they cannot so live, that while they do remain together, there must be the position of superior and inferior, that I as much as any other man am in favor of the superior position being assigned to the white man.

We got no need for this piece of shit. Amerikan revolutionaries are reflected in Harriet Tubman, Frederick Douglass, John Brown, W.E.B. Du Bois, Malcolm X, MLK, Fred Hampton, Goyaałé, Helen Keller, and many more.