It's worth reading some of the interviews with the director, who is apparently mortified by the whole thing. (Eg, this one.) He had switched the casting of The Ancient One because the actual character from the comics was such an out-of-date stereotype (the same way he updated Wong) that he felt he needed to make some changes, and miscalculated. Having been, let's say, educated by the controversy, he's been refreshingly free with the mea culpa's.

So personally, I'm inclined to forgive him -- it's a nice change to get an honest embarrassed apology instead of the typical stonewalling. An educable moment for Hollywood...