Simplistic partisan analysis. As always there is much more to the story. Correa is in serious political trouble back home. Leftism in South America has been simmering down. There are a lot of reasons why hosting Assange does not look like the great PR move it did to him four years ago.
Probably also did not think it through beyond a few months and didn’t expect this to be going on 4 years later. Will Assange ever be free to leave without legal jeopardy, or does Ecuador have to decide whether to boot him out at some point? Or do they continue to play host for years and years?
It may be as simple as the Commie Leader of Ecuador would like to see a Commie lead the US.