Both wireless headphones and laptops have downsides that you pay for the convenience of portability/ease of use. Sometimes it's worth it, sometimes it's not.

I use laptop only when I don't have any other option (traveling, meetings) and there is no way in hell that I'm going to work on a unplugged laptop for more that few hours simply because I don't like the ergonomics, performance and lack of "monitor space". This means that "battery life" after certain treshold (few hours) is useless for me and not something I would consider while buying one.

I understand that different people have different workflows and battery life is crucial for some of them, but it's not something everybody needs.