From the linked url > Lower end devices will take more time to meet our requirements since the updates and security features aren't as good. It's mostly due to

From the linked url > Lower end devices will take more time to meet our requirements since the updates and security features aren't as good. It's mostly due to how Qualcomm handles it. The latest Snapdragon flagships have the best security features. We'll also need Motorola to start paying them for longer updates below flagships