Bonin was showing himself to be extremely resilient to coming back to reality and rationality. He needed to be physically restrained. He was far too stuck in his head to rely on anything less.

Alternatively, we just kinda have an understanding that if your pilot goes into panic, and the copilot can't figure out a way to get them out of it, everyone dies.

Of course, then what if they panicking pilot decides they have to restrain you so they can continue what they are doing?