I was literally writing this yesterday. 
We’ve got a “privileged”/default tool in the ecosystem already, and that’s a big part of why it serves as the common denominator.
I don’t think we can have pip combine all the workflows/innovations into one thing – that isn’t tractable or reasonable, but (1) pip build, (2) pip publish, (3) pip lock/pip resolve and (4) pip sync will get us ~90% there and it’s not an intractable task as I’ve seen people claiming in the thread earlier.