Gruber makes it clear, http://daringfireball.net/linked/2016/09/08/airpods-hands-on, the only thing proprietary is the pairing between the iPhone and Airpods with the case. Other than that, these are just plain bluetooth headphones. They will work fine with other devices, and other devices will work fine with the iPhone 7.
Where have you read that iPhone7 bluetooth is proprietary? How can they be backwards compatible if they aren't bluetooth? I can't seriously believe Apple would release a phone that is incompatible with the many excellent bluetooth headphones out there.
So my Bose headphones are not going to work with the iPhone 7?