I do realize that this is a community forum. And, honestly, I think this question is appropriate here:
After all, I am not saying that Nexus has a bug (where an issue tracker like https://issues.sonatype.org would be more appropriate), but merely that it doesn’t behave as expected. This may be a bug but just as likely it is me misreading how a configuration option like maximum metadata age or auto blocking enabled is supposed to work. Maybe a fellow Nexus user can help me out here or has been facing similar issues.
(That being said, if you really think this kind of question is off-topic, then please add a pinned message to the category spelling out what kind of questions you want and what you don’t want. Personally, I have a hard time telling why my question is inappropriate and, e.g., this one is not.)