I should be able to buy a pair of headphones with built in streaming capability and be able to cast from HomePod or my phone with near gigabit bandwidth over Wi-Fi 6, and have zero concerns about range anywhere in my home.
Bluetooth uses about half the energy per bit transmitted compared to wifi. So, using wifi would cut all your run times in half or increase your battery size. The data transmission is the dominant power consumption of wireless ear phones.
That's silly. This would imply that there's no point in ever having any form of wireless data transmission with more bandwidth than the totality of your senses can intake at once. Obviously it could be used for more than just transferring audio data. But bandwidth isn't really the point anyways. It's about connection quality and range, which Bluetooth will never be able to achieve by design. I would gladly sacrifice battery life for headphones that "just work" with zero effort connectivity at all times, in the same way my laptop seamlessly connects to Wi-Fi.