Deleted files not considered with wanted="anything"

My understanding is that a preferred content value of "anything" (or equivalently the standard group "backup") should consider deleted files from a remote as wanted. I'm not a heavy user of preferred content myself, so this understanding is based primarily off of the preferred_content/standard_groups documentation saying

### backup

All content is wanted. Even content of old/deleted files.

`anything`

At least with the scenarios I've constructed, I haven't been able to find a case where old files are considered. As an example:

cd "$(mktemp -d ${TMPDIR:-/tmp}/gx-XXXXXXX)"

git init a
(
    cd a
    git annex init a
    >foo && git annex add foo && git commit -m"add foo"
    git rm foo && git commit -m"delete foo"
)

git clone a b
(
    cd b
    git annex init b
    git annex wanted . anything
    git annex sync

    set -x

    git show git-annex:uuid.log
    git show git-annex:preferred-content.log

    git annex find --want-get
    git annex get --auto
    git annex unused
)

[...]
+ git show git-annex:uuid.log
17fae615-a90b-405a-85c2-9d0f28246bdf a timestamp=1586190820.385256186s
1f0ad7d6-31ba-4d7e-a2e6-ab6acb3338c9 b timestamp=1586190820.750487084s
+ git show git-annex:preferred-content.log
1f0ad7d6-31ba-4d7e-a2e6-ab6acb3338c9 anything timestamp=1586190820.867633471s
+ git annex find --want-get
+ git annex get --auto
+ git annex unused
unused . (checking for unused data...) ok

The output above is with 8.20200330, but I saw the same result when I tried with 7.20190819.

I haven't been able to think of another way to interpret "Even content of old/deleted files", so I think at least this is a documentation bug.

Related DataLad issue

Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)

Yes. Thank you! :>

done --Joey