Progressive Politics

The entire logic of using an "Uncle Tom" on Obama is that he is expected to treat black people better because of being himself black, but is not doing so, "hence" he is like Uncle Tom.

It's Racist to expect that as a black person he would treat black people better both because of the "he's black hence" part (i.e. expecting that what one does depends on skin color) and the expectation that people should help people of the same skin color (which when that skin color is "white" is literally a white supremacist dog-whistle).

In summary, the entire concept of Race Traitor - which for Afro-Americans is encapsulated in calling them an Uncle Tom - is Racist as fuck, which is probably why even the NAZIs would throw around accusations of people being Race Traitors when they were deemed Arians but did not support the NAZIs.

The non-Racist take is to expect that people in positions of power should help people in need, quite independently of the race of any of them. From that viewpoint, which has no "Race Traitor" concept, Obama by his own actions is just another sleazy sociopath.