Same as today I think, we can't remove the element or remove links as long as it will result in an overflow of the hub.
How I see it is that technically the "destroyed" elements are not destroyed, it is only a state indicating they are "broken and can't be repaired" so we can imagine that the content is intact. If it is the case, I just hope they handled well the transfer of the content and links when replacing a broken container/hub.
If not, there are multiple scenarios where destruction of the containers would be problematic for the distribution of the content in the remaining containers:
- when an item is too big : like a Territory Unit on a 5 XS containers hub, does it get lost?
- when the entire content is too big : how to choose which items get lost?
edit: talents bring the same problem, from which player are they applied?
At the end, should the content be lost? If the container/hub are technically really destroyed (ie totally disappeared) yes, but apart the previous problem, we need a way to know an element has been destroyed, hence this mechanism. If it wasn't here, our ships would slowly decompose without knowing what elements are missing, repair unit could be handy there but maybe too hard for new players just starting.