Bkool is a competitor to Zwift, and I don’t think they speak. Bkool BLE only works with Bkool Simulator and not any of the other simulators AFAIK. I don’t think Zwift specifically supports Bkool trainers, but via ANT+ FE-C they support any brand, as it is a “standard” for controlling fitness equipment. Other trainer brands also use proprietary implementations of BLE, but are of course willing to share it with Zwift as to sell more hardware. Bkool wants to keep you on their simulator, as this of course gives them a steady cash-flow through subscriptions. Therefore, there is little incentive for them to open it up for Zwift.
The new Bluetooth FTMS should make Bluetooth work across brands, like ANT+ FE-C. This however requires a firmware update of the trainers, and I don’t think the old Pro and Classic will receive new updates.
As far as I know, only the Elite Direto (and perhaps Drivo 2) already supports Bluetooth FTMS.
I don’t get it, why people is so keen on running Zwift on an Apple TV with it’s many limitations, where you can’t use your ANT+ equipment, lower graphics quality etc. You’ll probably end up having to buy new stuff to make all your older stuff work. For the price of that and the ATV 4K, you could buy a pretty nice second hand PC, which is a much more versatile device.
Why not get Apple to support ANT+ FE-C instead? I’m pretty sure the communications chipsets inside the iPads/ATVs are capable, unless they are made by Apple. But if Apple has to pay a license fee to use ANT, it is probably never going to happen, as they focus MOST on maximizing profit!