It's not just you. My initial reaction was that it meant "we have come far", meaning that "we are close". My next thought was "That can't be right, he must mean we are distant from the goal."

Why is this so ambiguous? Far and distant are synonyms, right?

I suspect that it's because you can use "far" to describe a path you have traveled, in a way you can't with "distant". "We have come far", "We are far along our journey." So that "far" can mean far from a point of origin as well as a point of destination. Whereas "distant" only means distant from that point of reference.

So I thought the title was ambiguous without a preposition to clarify "far": "far away", for example.

Perhaps it's in the framing of the question: "the current state of x" implies that it's being considered as an ongoing process, which implicitly has an origin and a conceivable end.

Also, putting the subject as "we are..." puts it in the frame of an ongoing journey. If you say "That lighthouse over there, it is far." there is no ambiguity that the lighthouse is distant from us. Also "Effective computer vision: it is far" is not really ambiguous.