Posted a patch upstream: kbuildsycoca: Ignore last modified time when set to UNIX Epoch (!87) · Merge requests · Frameworks / KService · GitLab
You can try the fix by downloading the RPM from https://koji.fedoraproject.org/koji/taskinfo?taskID=87087243 and then running:
$ rpm-ostree override replace ./kf5-kservice-5.93.0-2.fc36.x86_64.rpm
and reboot