First let's understand the concept of Metatheatre from Wikipedia: "Metatheatre, and the closely related term metadrama, describes the aspects of a play that draw attention to its nature as drama or theatre, or to the circumstances of its performance. "Breaking the Fourth Wall" is an example of a metatheatrical device."
This film reminded me of Luigi Pirandello's 'Six Characters In Search of an Author', although it must be noted that 'Kul' is far inferior than the above mentioned, I saw an attempt to construct something akin to Pirandello's masterpiece. The characters could've been explored further especially that of the Husband, but I also understand the constraints of Netflix presentations.
I personally thought the film was decent, not good or bad but decent. I was shocked to see so many people reviewed it so badly then then again I was remembered that Pirandello's play was called "madhouse" when it was first performed in 1921. Perhaps without my prior knowledge of these I would've reacted in a similar way.