Funcom’s recent messaging on the topic:
Why anti-fence foundation stacking?
Fence foundation stacking was primarily changed due to server and client performance.
When a lot of building pieces are stacked in the same location it can cause clients to crash, and servers fail to load buildings correctly.
One of the primary reasons we made this change is to reduce those crashes and failures to load buildings. This strategy was an exploitation of a bug that we unfortunately did not get to fix properly before it became the expected way to play the game for a lot of veteran and high end players.
With this change, we know that the pace of PVP raids will change but making the changes will allow us to monitor the situation and player expectation.
We can also make future changes to either building health, siege damage from all sources, or both based on the feedback we get.
If you would like to keep an eye on the ongoing conversation about the anti-fence staking feature, you can [continue to] check out this thread…
Thank you again for always providing us with valuable feedback and for helping us improve the world of Conan Exiles.