Bastien writes:
> No, (require 'org-loaddefs) is never needed IMHO.

It is if you are using Org from Git and you only want the autoload
definitions pulled in on startup and not the whole of Org plus most of
its dependencies.  This is what a

(require 'org-install)

did before the change to org-loaddefs.el.  You can't rely on some older
Org version in Emacs or whereever to supply the correct autoload
definitions, so you eitehr need to

(require 'org-loaddefs)

which is horribly wrong in case you're not sing Org from Git; or

(require 'org)

which is pulling in too much stuff on startup.

Org from Git is currently missing the first-level autoloads file that
was implicitly introduced for all other use-cases with that change
(loaddefs.el for vanilla Emacs and org-autoloads.el for package
manager).  I propose to re-introduce org-install.el for this purpose for
standalone Org.