Everyone is up in arms about the use of bark boxes to hop across walls... completely avoiding the REAL ISSUE
The issue isn't that PVPers are getting into walled claims, it's that it takes zero effort for them to get out. All they have to do is type /stuck and POOF they magically appear outside the claim they are attacking. This removes any incentive for smaller groups to build claim walls.
"Let them get inside our walls all they want, life is feudal, but hell if it isn't cheating to use a console command to escape..."
Solution: When in another guild's claim, remove the /stuck command and make the Prayer for Homecoming the only way to 'unstuck' oneself and/or escape. This forces attackers to physically escape walled claims if they want to keep any loot, while giving defenders an opportunity to regroup and counterattack.
TLDR
/stuck is ruining base defense not bark boxes, fix this by replacing /stuck with Prayer for Homecoming when on another guild's claim
EDIT: link to reddit post