I haven't seen this theory thrown around yet.

When Luo Ji wakes up a couple hundred years in the future, the entire personality of the human race has changed. They're exceptionally confident about beating the Trisolarans. It was such a dramatic shift that I kept waiting for it to be revealed that Hines' mental seal machine had been used on the entire human race - or at least on those in power and in the military - to convince them that they could be victorious.

The reveal never came, but I still wonder if this happened. Yes, they're confident because of the size of their fleet, but this doesn't seem enough to warrant the level of assurance everyone shows. The interactions Luo Ji has with different people about how humans will win the war all sound sort of like canned responses.