You are absolutely right. If people do not care about the truth, I cannot convince them otherwise by providing arguments about why there is such a thing as truth. They have to decide for themselves that the truth matters as an end in itself.
For the last 39 years. my first allegiance has been to the truth, and that will remain the case until the day I die.
2PC is not “my preferred theory”. That is pure old-paradigm-thinking. The whole point in 2PC is that it might actually be true, not that anybody prefers it.