I'm not a user, but I have experience with one use-case where I'd imagine they're very useful:

When maintaining an open source project, there's often a little bit of tension between making the development experience more productive for you, the maintainer, and more convenient for new contributors. Using a more complex toolchain might make things nicer for you as someone who works in the codebase every day, but adds overhead to anyone who just wants to make a single contribution related to their own work. I could imagine having a "click here to develop" option would help ease that tension.