We already have that is called Pharo or Glamorous toolkit.
I guess a way to describe it is imagine a virtual machine, like vagrant... that comes preloaded, with your editor, your database and every app you coul imagine.
Then each app is an object that is callable from your peogram.. is like if you were developing an app and could import an excel function in your own code... even better script excel from your own code.
Thenwhen your app is ready, just deploy your machine.
Smalltalk is an elegant weapon of a more civilized time.
An environment for software development is much more than an OS. There are tools and systems that are installed onto it. People also have preferences, so there really isn't a one size fits all.
A better question may be "How do you maintain parity for your developer systems?"
This is more complex than using something like Packer or Ansible to create a consistent VM. How do you know if the developer changed something manually?
This was the point of the question :) To see what questions we need to ask if we're designing a software development environment in 2021. It may well be true that the current paradigm is sufficient: I was just curious what else came up.
Thenwhen your app is ready, just deploy your machine.
Smalltalk is an elegant weapon of a more civilized time.