Why does this proposal belong in 262, but not the rest of Underscore/Lodash?

[sffc]

This proposal is basically taking one of the convenience methods from popular JS helper libraries like Underscore.js and Lodash and putting it into 262.

Why uniqueBy? Why not zip, chunk, or any of the other convenience methods not yet covered?

[ljharb]

Userland is where many of the array methods came from - I think the automatic answer is "probably all of them should be included, but in independent proposals"?