If something cannot be tracked, then it should be allowed.

Wow...
Finally, I heard a well-formulated explanation of the principles behind creating laws and rules.
Instead of quoting Roman writers and historians, let's look at more recent history. Tukhachevsky used to say something like, "If you declare a threat, you must be prepared to carry it out, otherwise, never make empty threats..."
In my opinion, applying this to the current situation:
Controlling the execution of this condition (not being able to view castles) is practically impossible, so we should simply allow it, declaring it as a feature (moving it from the category of conditional bug-features, or feature-bugs...). To appease the souls and consciences of those who are zealous about purity, we should declare it everywhere so that newcomers are aware of it and everyone is on equal footing.
END OF MY OPINION.