CP 28 moved Cobertura to a profile called "reporting". The profile was activated by default, but could be disabled by using
-DskipReports=true or -P!reporting IIRC, the idea was to move expensive (long-running) reports to a profile that could be disabled if necessary. However Cobertura causes problems with some projects, and the project seems to be unmaintained, so perhaps it would be sensible to disable Cobertura by default. In which case the profile and property should be renamed to reflect the fact that it only affects Cobertura. Possibly even drop Cobertura entirely from the parent POM. However, I think it is important that some code coverage tool is used.
