The command org-kill-note-or-show-branches bound to C-c C-k when used to show branches also expands headings tagged with :ARCHIVE:. This is contrary to expectations, as the manual states:
‘C-c C-k’ (‘outline-show-branches’) Expose all the headings of the subtree, CONTENTS view for just one subtree. CONTENTS view when using TAB cycling does not expand archived headings. Can be reproduced with a .org file containing: * Foo ** Bar :ARCHIVE: *** Baz Emacs : GNU Emacs 26.3 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.10) of 2019-08-29 Package: Org mode version 9.3.1 (9.3.1-elpaplus @ /home/ionasal/.emacs.d/elpa/org-plus-contrib-20191226/)