I don’t think that Darwinism can rightly be defined as Positive Selection Dominated Change. Darwin’s theory had positive selection, negative selection, and even drift.
Also, he was trying to explain adaptation, and Darwinian selection still appears to be the only game in town as far as adaptation is concerned.
Further, he wasn’t concerned with evolution at the same level that Kimura was dealing with so Kimura did not falsify Darwinism because they are not about the same thing. Could we say there is an analogy in physics? Has Newtonion (classical) mechanics been falsified?