homsar
Apps don't actually ask for sensor permissions. The ability to deny sensor access (i.e. force results to 0) is a GrapheneOS feature.
https://grapheneos.org/features#sensors-permission-toggle
To avoid breaking compatibility with Android apps, the added permission is enabled by default. When an app attempts to access sensors and receives zeroed data due to being denied, GrapheneOS creates a notification that can be easily disabled. The Sensors permission can be set to be disabled by default for user installed apps in Settings > Security & privacy > More security & privacy.