Microprofile Metrics in Wildfly 17.0.1 in combination with JPA 2.1 is currently broken. The fix done in WFLY-10964 (https://github.com/wildfly/wildfly/commit/9dac9810796469ab45cb2b6e0fde926b9d193561) should be applied to the JPA 2.1 version (wildfly/jpa/hibernate5) as well.

Also, the same faulty code is present in Hibernate: https://github.com/hibernate/hibernate-orm/tree/master/hibernate-jipijapa/src/main/java/org/jboss/as/jpa/hibernate5/management
Not sure why it is in there as well, but it probably should be fixed or removed.