Impossible to install symfony/symfony with Symfony Skeleton

[bocharsky-bw]

In docs I see I'm able to install all the Symfony components with:

composer require symfony/symfony

See: https://symfony.com/doc/master/components/using_components.html#using-all-of-the-components

But in Skeleton's composer json I see it's impossible:
https://github.com/symfony/skeleton/blob/de1ec4a4f994246d9596a1c9bfd3f1f1cf6d3beb/composer.json#L53

Can we make docs clearer here? Maybe some kind of note how to achieve it with symfony/skeleton?