I wonder if this kind of thing is found in other languages. for example i can't think of any in French (i am French) even "it is what it is" which I would translate by " C'est comme ça" (it is like this)
Something like the following repetition is ultra common:
"C'etait bien ?" (What is good?)
"Oui c'etait bien. Enfin, pas 'bien bien' mais... Bien". (Yes, it was good. Well, not "good good" but... Good).
The "x is x" is ultra common too, say to a kid, when it really needs to go to bed:
"J'avais dit dodo et dodo c'est dodo!" (even if it's not proper french, it's a typical way to talk to kids: "I said bedtime and bedtime is bedtime").
Even with french "verlan": *"Il etait relou. Pas relou-relou mais quand meme un peu relou!".
Also I'm sure I hear this one all the time: "Quand faut y aller, faut y aller!".
It's everywhere in french.
The formal rules of the language discourage tautology though. It's considered ineloquent, so it's not very common.
And then qu'est-ce que c'est takes it to another level - what is this, that this is?
إِلِّي صَارْ صَارْ
Which translates to: "Whatever happened, happened."