>
> > In the meantime, is there a command that will close all drawers, even
> those
> > that are open in sections (headings) that are closed?  I searched but
> > didn't find anything.
>
> org-hide-drawer-all
>

I don't seem to have that command.  I'm using Org mode
release_9.6.10-835-gf3de4c.

I grep for org-hide-drawer-all there is the following entry that seems to
imply the command is obsolete:

(define-obsolete-function-alias 'org-hide-drawer-all
  'org-fold-hide-drawer-all "9.6")

If I try to run the command using

  M-x org-hide-drawer-all

I'm told "no match".