Unfortunately air tags only work in the Apple ecosystem.
That's not true - Tracker Detect is available for android, so even car thieves with an android can find your airtag.
Tracker Detect only scans for AirTags when the user manually requests a scan. Car thieves and other users who do not want to be tracked by AirTags would be better off using the AirGuard app on Android, which scans for AirTags and other Bluetooth tracking devices in the background automatically:
https://github.com/seemoo-lab/AirGuard
AirGuard is a FOSS project developed by the Technical University of Darmstadt.