Sort of; if you find a lost AirTag, you can get the contact info from an Android device via NFC: https://youtu.be/ehv3zQAa9zM?t=528

You can use NFC on an Android device to read the owners details on a lost AirTag.

The firmware was recently dumped so maybe someone will figure out a way to build an alternative network to Find my.

Samsung has their own system: https://www.samsung.com/us/support/answer/ANS00088244/

But nothing interops with AirTags yet and I'm 100% sure they never will, since AirTags relies on Apple's backend to work. The actual devices are the simplest part - and you can get 3rd party AirTags already.