Most defense contracts require 40-hour work weeks. A company can't ask you to work more than 40 hours typically or be in breach of contract (being unfair to the competition who bid on the contract). So yes, when I worked on DoD contracts I was in at 7am, out at 3:45pm.

In general, yes, defense contractors are better. But they also have a old school thinking about compensation and equity, so it’s a trade off. Not sure about Palantir specifically though.