I have a PR open (https://github.com/wildfly/wildfly-core/pull/4636) that hides properties that were long ago marked as deprecated. To be clear, the properties themselves are not deprecated, but direct access has been. There are getters and (where appropriate) setters that should be used instead. Most of WildFly full has already been updated to use the methods for accessing the properties (with a few stragglers addressed at https://github.com/wildfly/wildfly/pull/14378). If you have a subsystem not in the wildfly repo or any project that depends on WildFly Core that uses AbstractAttributeDefinitionBuilder or any of its children, it would be prudent to verify your usage to ensure you are not using the now-hidden properties directly.
If you have questions or concerns, please comment on the PR.
Principal Software Engineer
Red Hat JBoss EAP