It's never tomorrow. It's always and only today.
Look up to heaven and down on earth, and they will remind you of their impermanency. Look about the world, and it will remind you of its impermanency. But when you gain spiritual enlightenment, you shall then find wisdom. The knowledge thus attained leads you to the Way. - Sutra of Forty Two Chapters
Of course truth matters. Only, not in the obvious way. It matters in that it is what keeps individuals sane. Sane, while whole groups, nations, the entire world, cultivates the prospect that insanity is a reasonable way to live.
No, truth will never be proved. Not the way we'd like it to be. Instead, there is inference, reasonable probability, justifiable action, good will and good faith integrity that refuses to affirm what you know is not true.
Maybe that's it, that's the limit of human ability -- not to know and prove the truth, but to not be diverted into surrendering to what is not true.
A withholding of assent. A standing off to the side as propaganda and illusion barrel down the street. Often, standing alone there.
There is nothing to prove.
There is only a place to stand.
Solitariness moving the world.