Ecuador sheltering Assange is more about Ecuador having a stronger bargaining chip with the US in future deals than anything else. Ecuador isn't some bastion of liberty. Far from it, actually. They're doing it to make a statement to the US and internally to themselves. I'd be willing to guess that Ecuador would turn Assange over to the US in a hot minute if the getting was good for them. I think the reality of this situation is that the US doesn't really want Assange all that much. He's a non-player wrt Wikileaks any more and people are already forgetting who he is.