In general the second drivers haven't been good enough this year. It's been all Hamilton vs Verstappen. If you have two teams fighting for the title, then the performance of the second driver is crucial. Bottas should be taking points off Verstappen every time it's a circuit where Mercedes dominate, and Perez should be doing the same to Hamilton every time it's a Red Bull circuit. It was nice this time that both second drivers played a valuable role.