Being unique doesn’t necessarily imply ‘good’ or ‘better’. If the rumors are true and the Air happens to have inferior specifications, tech enthusiasts would at least avoid it. Even regular customers would if the battery life suffers.
MacBooks and iPads have ample space within them to be slim while still accommodating a decent battery. The SE 2 and 3 serve as living examples of powerful chips housed in tiny battery phones, but the experience isn't that good.