I'm talking about Buddhist philosophy, which is supposed to be a logical reconstruction and defense of what happens on that behavioural path. So there are indeed two separate things here, the philosophy and the practice or experience. I don't deny that Buddhists can be trained to be selfless or even that they inevitably become selfless and compassionate when they're enlightened.

The issue here is the search for the best explanation of what's going on in that practice. There's the standard Buddhist account, and then there's mine. Which account is best, according to philosophical standards?

Now, if you presuppose pragmatism, you can say the proof is in the pudding, so there's no need for a Buddhist dense against my charge of nihilism or incoherence. The results would speak for themselves, in that enlightened Buddhists tend not to be insane, traumatized, or alienated, due to their extensive training. That's fine for pragmatists or consequentialists.

Those looking for deeper conceptual understanding, who aren't themselves hyper-skeptical, empiricist Buddhists are free to wonder, as I do, why an arhat should be expected to be compassionate and joyful, given the basic Buddhist epiphanies. The training must force that behaviour on them, but I can explain that on psychological and political grounds (via Leo Strauss). The inner experience of adopting the cosmic perspective would entail nihilism and a transhuman condescension towards both egoism and the social respect for laws, morality, civility, etc.

Sure, social laws are needed to protect people, but why would people matter more than rocks and the vacuum of outer space, given the enlightened perspective that takes up the realization that all things dependently arise and defy their corresponding concepts (by being empty of essential meaning)?