> How about we discuss instead whether or not these kinds of castles are fun?

Well, like Newton said this ends in a religious war. I don't want to polarise so feel free to correct my word choice.
You want the conservative castle construction, big bottom, thinner top, everything more or less based on physical laws. Even if that means more limitations, like you said:

> but actually outright forbid this kind of castle building.

More concepts are thinkable like collapsing buildings in midair.
Am I right?

I, on the other hand want some abstract, not everytime realistic and sometimes even awkward looking castles. I don't feel like suppressing some creativity by gaining realism. And I still point out that tactics like 'overbuilding' another castles are already possible but due to practical aspects (duration and material requirement) aren't used. That are just balancing aspects.
To your fear of awkward decisions, I think I can overcome it. Judging from the thickness of that castle part, I think it's pretty clear that you can shoot like this:
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but not like this:
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