As far as I know (native AmE), the original expression was "everything but the kitchen sink", which evokes the idea of taking everything in the kitchen and using it all in a recipe, only stopping short of dismantling the kitchen itself.
Whether through mishearing or laziness, the "everything but the" part has been dropped. I only noticed it in the last few years, but maybe it's been happening for a lot longer than that. So it's now totally the opposite: the only thing in the expression is the kitchen sink, i guess suggesting that there's a bunch of junk in the sink?
But this title is even better. We have abandoned all pretense of caring about the meaning of the expression. In 2021, Chuck Schumer is going to call Mark Zuckerberg in to testify, and he is going to physically hurl a big metal sink at him.
I know that language evolves and stuff, but it's pretty funny to see such a silly corruption of an already-kind-of-silly idiom in a "serious" title.