I also thought the same. Atalanta couldn't find the back of the net because Inter defense was very strong. However, after the first goal in the second half, that was when I started losing hope in Atalanta because Inter was able to spot out their weak points and took advantage of it. Currently, I don't think there's much hope for Atalanta to win Scudetto this season, because Inter wouldn't let that happen.
I really loved how Inter Milan approached the game, it showed that they were intentional and knew exactly what they wanted which was to win the game and remain top of the table. At least Inter Milan can breathe a little as they are ahead of Napoli with 3 points and a significant amount of goal difference in their name.