>I'm not sure the set of people who care about out of the box and the set of people who would be future maintainers is a very large intersection ...
Yeah that's the common refrain. It's just gatekeeping in my experience. A certain demographic tends to view using the terminal or using bad UIs as some sort of badge of elite status, and sneers at people who want to spend their workday looking at visually-pleasing UIs.
>Also, what is a good out of the box experience for emacs?
Well, a GUI that doesn't look like it's stuck in 1997 for starters. Off the top of my head, handling long lines without chugging, being async/multithreaded so a network request doesn't lock up the entire fscking UI, offering CUA-mode by default for easier onboarding, fixing the often absurd terminology in the docs (frames/windows/panes/yank means paste/etc.), and probably a few others I can't think of.
Have a look here: https://code.visualstudio.com/docs/getstarted/userinterface
That's just an immensely better UI, by default. To achieve even 80% of that in emacs you'd need to spend time configuring at a minimum treemacs, an lsp client, breadcrumb-mode, minimap, probably project.el or projectile, magit, one of the tab-bar modes, and a bunch of niceties like showing line numbers by default, to say nothing about a better theme.
All that stuff should be built in and there's no good reason other than "the emacs developers are overworked already" for them to not be included.
Imagine showing someone the editor above, and then showing them this. Which one do you think they'll choose?
https://www.gnu.org/software/emacs/images/teaser.png
It just looks amateurish and unpolished. It looks like it's janky and doesn't work very well. It's just unappealing in any modern sense.