CT:s are increasing the size of transactions significantly, so there needs to be a breakthrough in that technology. Scripting is more difficult with mw, like enabling the lightning network. The rationale is to move privacy features on higher layers, enabled with Bolt12, Federated chaumian mints etc.
Discussion
On-chain you can still use CJs, like Whirlpool.
CT:s are implemented on Liquid.
So there is interest, but everything has trade-offs.
The funny thing is that privacy features were both born out of the bitcoin protocol and considered for it. So they are deeply concerned, but also extremely careful because of the trade-offs. Implementing a whole host of technologies at the same time will have all kinds consequences.
Coinjoin: Gregory Maxwell
Confidential transactions: Adam Back, Gregory Maxwell
Dandelion: It's a BIP that will probably be implemented in the future