1.9.1 - zonefile being read but not written to

[ѽ҉ᶬḳ℠]

debug: read zonefile /srv/unbound/zone files/root for .
debug: no zonefile /srv/unbound/zone files/root for .

That is with verbosity level 7 and no further insight of why unbound
reads the file location but does not write to it.
Also with an empty file provided it just reads that but does not write
to it. If there would be some issue with ACL permissions I would expect
such to show up in the debug log.

How to get to the bottom of it, or to remedy?