I think this is a point worth clarifying - we’re reasonably confident that no legal opponent could, specifically, destroy the wallbot.
This is because of the specific disallowances of robot-destroying mechanisms in the inspection checklist and rules manual. We’ve designed the current bot to handle the vigorous interaction possible from defense-focused opponents, and even that was not enough (see: 315G 6m base with ramps from Turning Point unable to budge the wall).
As of now, I’m still leaving the door open that a legal opponent could circumvent the wallbot, probably through some equally ingenious engineering. Even so, if the fear of losing to a wallbot is so high that teams design custom mechanical solutions into their robots, then I think that’s actually a point for Team WALL-E.