It is relevant because we know Amalek will only be killed when Mashiach comes. And when that happens the world will see the truth about Hashem and the fact that he was hidden for all these years.
That's actually a good point, but I'm not sure it changes the calculus... By killing Amalek after Mashiach comes, we'd be following the word of our Gd, our Bible. Given the point in history from which your analyzing it (i.e. after the arrival of Mashiach), the entire world would finally be privy to the ultimate truth.* However, at this point, we are not as fortunate. The various worldly religions believe
they are the ones who have it correct, and anyone else does not. To wit: The extremist Muslims believe that by killing all "infidels" they are following their Gd's command, and their "Bible." Religious Christians believe there will be a second coming... so on and so forth.
Now, as someone who is a Jew, I believe my religion is the one and only correct one. (Obviously, otherwise, I'd just switch.) That said, it's wrong to fault an entire religion for the actions of its extremist, fundamentalist sects.
*By the way, if everyone will be enlightened after Mashiach, that presumably includes Amalek. Are you suggesting they will throw themselves at our swords and willingly die because they know the soverignty of HaShem? Right now, the Muslims are the perpetrators, so why aren't we responding accordingly?
Who is we?