I think the discussion about what installation methods we recommend to newcomers is valuable, but it’s also mostly orthogonal to Scala CLI and to the SIP. Regardless, I’d like to state my opinions.
I doubt our ability as an organization to maintain an entire package manager. Coursier is a one-person project that encompasses both a dependency manager and a package manager. The dependency management aspect is a big and undermaintained project unto itself…!
On MacOS and Linux, I see little value in having yet another package manager. I personally have stopped using cs at all on these OSs. I’d much rather use a standard, robust package manager that I’m already familiar with, such as Homebrew, to install Scala CLI and sbt. And I’d much rather manage my JDKs some standard way, too.
Now that scala-cli can do things like run scalafmt and scalafix, the package management aspect of Coursier no longer provides any value for me. (It certainly doesn’t provide value in proportion to the amount of development effort needed to maintain it, going forward.)
On Windows, sadly, the question is more complicated. cs setup has real value there. Perhaps we should retire the cross-platform package management aspect of Coursier and concentrate on providing a Windows-only tool that does the equivalent of cs setup.