[rado]

Meanwhile, the core lacks: multilingual, CDN support, caching. Essentials.

[mtberatwork]

CDN support out of the box isn't essential, most sites will never achieve the kind of traffic that merits a CDN. However, to add to your list: database migrations, task queues, middleware, form validation, templating, dependency management, unified plugin framework, etc. No lack of callback soup though.

[LordAtlas]

Even something basic like a way to categorise and manage your media library is missing without freakin' plugins.

[chiefalchemist]

Those don't belong in core either. Core should focus strictly on the being a rock solid foundation. Plugins are there to supplement that. That's the beauty of the architecture. Or at least, is supposed to be.

WordPress should not have the same mindset as Jetpack. Oops? Did I just say that?? ;)

[rado]

WP is useless without CDN and caching.

[chiefalchemist]

It depends on how you're using it. It depends on the resources you have for such things. WP can and will work without them.