A lot of it comes down to timescales and sequences of events, long term vs short term.
“I will incur a little suffering today, but my well-being will be much better tomorrow”.
“We need to get rid of the <undesired national or social group> at cost of suffering, but our nation will have bright future as a result”.
People can be tricked into doing unspeakable evil to themselves and others if they have incorrect predictions of the future well-being.
From the linked publication: “A localized suppression of vacuum entropy near the hull creates dS/dx > 0 outward”.
I don’t understand this part. My naive view is that localized suppression means S<S0 (surrounding entropy), or some local minimum. S0 is the same on both sides far away from this minimum. This means the gradient dS/dx is positive on one side of this localized suppression region, and negative on the other side, possibly in an asymmetrical way. But after you integrate dS/dx over x to calculate the total force acting on the region, it will be exactly 0. The same reasoning applies to the other side of the craft, where you have a local peak of vacuum entropy. The total “push” will be 0 + 0.