Yes but he's asking why the DEVICES don't incorporate the technology. If for example Apple could claim 8x battery life in their keyboard by adding a 10cent piece of kit you'd think they'd do it.
To fit the booster into the same space as a battery is cutting-edge, but to put a cubic-centimeter boost circuit next to your battery chamber is nothing special. If the boost circuit is too bulky, the battery is definitely too bulky.
