Coming from a STEM background, I want to defend the humanities. Prolonging life is possibly a worthy goal, but is it really a benefit where that life has no meaning? Many people get much more meaning and value in their life from the humanities than they ever do from the sciences (oh, and that in itself saves lives).
Given the competitive process involved (and those grant success rates seem very similar to what our lecturers told us about computer science research), it seems unlikely that the minister has sufficient expertise to second-guess any of the decisions made. It's easy to mock the research based on the titles, but to have succeeded I suspect most of them have other important aspects which meant they were selected. There will be a lot of context, and we lack it. Perhaps if we knew the full details we would be much more likely to agree with the decision to select them (if you think there's a systematic problem with the state of research, then it needs bigger reforms than a minister vetoing a few projects).
To my mind it is completely irrelevant whether the Australian taxpayer would prefer the funding redirected to other research - it doesn't justify specifically targeting the humanities, because the same could be said of a lot of STEM research (try selling research into an obscure problem in number theory to the average person on the street...)