State of zkSNARKs on Ethereum for private transactions

Hi everyone,

I first heard about zkSNARKs with zCash as a privacy tool. A few years ago, I read about collaborations between zCash and Ethereum dev teams to bring private transactions to Ethereum.

Nowadays, I still read a lot about zkSNARKs on Ethereum, but for a different purpose: scalability.

But what is the state of private transactions on Ethereum ? Is it still being developed ? Is it already there ? Or will it come "for free" with L2 zkSNARKs ? Or is it just put behind because scalability is a more pressing matter ?

I'm surprised that this is not really discussed (or maybe I'm just missing it in the flood). For example, what would be the regulatory implications ?

Thank you for your answers