Sorry for reposting but I can not find my original post and response. The response I received was that only AirPods and beats support two devices connecting to an Apple TV device. I find this response somewhat perplexing that a premium product like Bose can not have this functionality. From my research I suggested this was due to the version of Bluetooth being used (it requires Bluetooth 5). Can I respectfully ask for more detail on why Bose can not implement this function with an Apple TV. Is it a licensing issue, hardware issue in the headphones or a Bluetooth version issue?
While I'm not familiar with this particular issue, I would suspect that it's from Apples end. If the answer you have been given is that only Airpods and Beats (owned by Apple) are capable of it, then Apple probably want to work better within their own ecosystem and have more features to get you to purchase more Apple devices.
It's similar to how some Bose Soundlink speakers only connect to Soundlink speakers for party mode. You couldn't substitute a JBL speaker as the second. How Bose can use simplesync to connect NC700s to the Soundbar, but you couldn't use Apple headphones the same way.