ansible-core-2.12 requires all libraries used in Ansible modules/roles/playbooks to be built with Python 3.8, so we need to build and distribute python38-dateutil in RHV channels, because it's a dependency for ovirt-hosted-engine-setup, where we use ansible callbacks executed within ansible-core-2.12
AFAIU the only user of dateutil was ovirt-hosted-engine-setup. With [1], it does not use it anymore. Closing. [1] https://github.com/oVirt/ovirt-hosted-engine-setup/commit/00cf2690739e98772bf3c827e33ec0313baf5888
Mind you, this isn't purely a CodeChange. It does have the slight (IMO) disadvantage that the timezone offset is calculated only once, at ansible-playbook run start. So if you start it slightly before an offset change (e.g. from daylight saving time to standard time or vice verse), the log file will be wrong since the offset change onwards - will show the same offset instead of the updated one. But I think it's worth it.
("it", in "start it", isn't the full deployment, but a specific playbook. 'hosted-engine --deploy' has its own log file, which should be correct (it requires and uses python36-dateutil), and runs several invocations of ansible-playbook).
This bugzilla is included in oVirt 4.5.0 release, published on April 20th 2022. Since the problem described in this bug report should be resolved in oVirt 4.5.0 release, it has been closed with a resolution of CURRENT RELEASE. If the solution does not work for you, please open a new bug report.