He's not poisoning the minds of his kids, he's just being a realistic coach and not giving the kids false hopes. Small school teams don't have that big of a chance to get past bigger Schools so again they focus on making each individual better and getting those kids who have the qualifications, to make it to state!
I know if my coach was blowing smoke up my butt about how we could beat some team (when we had a snowballs chance in hell) I would question weather or not he should be our coach. When bigger schools come in and tear you a new one in a dual meet, you usually can tell if you'll beat them later on in sectionals or regionals.