He still talks about the Fremen though...Yes that's part of the discussion but Hawat starts off by asking if the baron knows why the emperor wanted House Atreides destroyed and then talks about the training of the troops by Ducan and Gurney to match the sardukar.
The talk about the harsh environments and Salus Secundus then comes as Thufir goads the baron to use Arrakis as his prison planet and for raban to squeeze the population.