Why after-init-hook is not invoked? (workaround is emacs-startup-hook)

Question

short story: The theme just did not show up automatically at emacs start, when it is invoked by an after-init-hook. However, with emacs-startup-hook it worked as expected:

(use-package heaven-and-hell
  ...
;;:hook (after-init . heaven-and-hell-init-hook) ;; does not work
  :hook (emacs-startup . heaven-and-hell-init-hook) ;; this one does

I run plain emacs (emacs -l test.el -Q) with a test script (modified from this question)

test.el

(defun buffer-hook-function ()
  (append-to-file (format "%s" (buffer-list)) nil  "log.txt")
  (append-to-file "\n" nil  "log.txt")
  )

(append-to-file "Running ...\n" nil  "log.txt")

(add-hook 'emacs-startup-hook (lambda () (append-to-file "emacs-startup-hook\n" nil  "log.txt")))
(add-hook 'after-init-hook (lambda () (append-to-file "after-init-hook\n" nil  "log.txt")))
(add-hook 'before-init-hook (lambda () (append-to-file "before-init-hook\n" nil  "log.txt")))
(add-hook 'window-setup-hook (lambda () (append-to-file "window-setup-hook\n" nil  "log.txt")))
(add-hook 'emacs-startup-hook (lambda () (append-to-file "emacs-startup-hook after window-setup-hook\n" nil  "log.txt")))
(add-hook 'emacs-startup-hook (lambda () (append-to-file (format "after-init-time %.2fs (printed via emacs-startup-hook)\n" (float-time (time-subtract (current-time) after-init-time))) nil "log.txt")))
(add-hook 'buffer-list-update-hook 'buffer-hook-function)

log.txt

Running ...
  (*scratch*  *Minibuf-0* *Messages*  *code-conversion-work*  *Echo Area 0*  *Echo Area 1*)
  after-init-time 0.03s (printed via emacs-startup-hook)
  emacs-startup-hook after window-setup-hook
  emacs-startup-hook
  window-setup-hook
  (*scratch*  *Minibuf-0* *Messages*  *code-conversion-work*  *Echo Area 0*  *Echo Area 1*)

So after-init-hook does not appear, but after-init-time seems to be set, which seems to come from an after-init-hook.

I still do not see why after-init-hook is not called. This question refers to the command-line processing part of after-init-hook, so I tried different configurations, terminals and (non-)window modes.

• Why after-init-hook is not called?
• Does this mean, other packages with init hooks can also fail?

Edit: Using emacs 26.2, Manjaro Linux 18.0.4 xfce

Update: after rewriting my theme and addressing an issue in spacemacs-theme, after-init seems to work so far via heaven-and-hell. emacs-startup hook had other issues like additional syntax highlighting via prog-mode-hook did not work.

Update 2: The example test.el perhaps always fails. If you run without -Q it is invoked: emacs -l test.el:

Running ...
<snip>
  after-init-hook
  (*scratch*  *Minibuf-0* *Messages*  *code-conversion-work*  *Echo Area 0*  *Echo Area 1*  *load*)
  Running ...
  (*scratch*  *Minibuf-0* *Messages*  *code-conversion-work*  *Echo Area 0*  *Echo Area 1*)
  after-init-time 0.06s (printed via emacs-startup-hook)
  emacs-startup-hook after window-setup-hook
  emacs-startup-hook
  window-setup-hook
<snip>

Answer 1

Why after-init-hook is not called?

It is called, but it's called before test.el gets a chance to modify it. (elisp) Startup Summary:

 17. It runs the normal hook `after-init-hook'.

 [...]

 21. It processes any command-line options that were not handled
     earlier.

 [...]

 25. It runs `emacs-startup-hook'.

"command-line options that werer not handled earlier" includes -l test.el. So by the time you are adding to after-init-hook it is too late.