some dirs don't get deleted with make-delete-old

From: void <void_at_f-m.fm>
Date: Fri, 08 Dec 2023 12:16:50 UTC
It seems some dirs don't get deleted with make delete-old:

# yes | make delete-old

[...]
/usr/share/doc/atf
rmdir: /usr/share/certs/blacklisted: Directory not empty
/usr/share/atf
[...]
/usr/lib/debug/lib
rmdir: /usr/lib/debug/boot: Directory not empty
/usr/lib/debug/bin

is this an error?

context:
source upgrade from stable/14-n265798 to stable/14-n265929 on arm64
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