Obsidian/Joplin does NOT support manual/arbitrary sorting of folders or notes

When I finally decided to try Obsidian, I discovered that it couldn't sort folders (except for the default alphabetical sorting). Further searching revealed that most note-taking software (including Joplin) didn't allow manual or arbitrary sorting of folders or notes.

I believe manual or arbitrary sorting is a basic function that any bookmark manager or note-taking software should provide.

Why can't most software do this? Is it that difficult?