“We” is, if anything, a relationship between individuals. A relationship cannot act, only actual humans can. To say that “we” are building roads, schools or hospitals, therfore, doesn’t mean anything. It’s just a snakey rhetorical trick to make people feel a false sense of community, or to take credit for something that the speaker has not done.
Recently I visited Angkor Wat, a famous temple in South East Asia. The tour guide said “king X” built this. He didn’t. He payed others to build it. If he built it, I built the smartphone I bought recently. I also built the laptop I’m writing this one, and the pipe that I smoke my weed from.