Golden State's defense in the paint was horrible, and they gave up a lot of fast breaks in the 1st half. Their defense was improved 2nd half.
Remember GS was without their best rim protector and Cleveland only scored 42 at the half. It doesn't matter where those points are coming from, holding a team to 42 in the half is good defense. Sure, I agree that GS didn't play great defense this game, but their defense was solid. Also, remember GS likes to play small lineups without centers and for most of the game they did not have a true big man on the court so they allow more points in the paint.