I've asked here before about confidential TXs, Pederson commitments,...etc and how the fee is determined
People answered they don't know of a real implementation
So, why no one simply implemented them (I mean by suggesting a BIP)
Is it simply due to lack of interest?
I mean all of that was back in 2018, but maybe now no one really demanding confidential TXs in Bitcoin, or what?
Confidential transactions have been implemented on the Liquid sidechain, and a more scalable version based on Mimblewimble has been implemented as a recent soft-fork in Litecoin. The corresponding LIP [1] could be "ported" to a BIP if there was sufficient interest, but it does seem that such interest is lacking...
[1]
https://github.com/litecoin-project/lips/blob/master/lip-0003.mediawiki