Because if you have a communications protocol which is less power hungry (BTLowEnergyAudio vs current BT), paired with the new LC3 codec, you may be able to implement more features like a better crossover and amp which will use that (now)surplus energy (at the same time giving you more resolution). Or keep the same cross/amp and give you ANC working with 4 or 6 mics while still giving you 6/8 hours on a single charge in a pair of buds. It’s a balance of sound/features/battery, I guess.
I don’t know many details on their implementation but, for example, the Pi7 can only reach around a four hour battery probably because the crossover/amp is munching on that battery to give you that type of better amplification and resolution in the sound. And while they still give you all the other features, if you want their SQ you have to live with a 3 hour battery.
We all want 10 hours on the buds + 40 hours in the case, or better. But then we also want good ANC (which has at least two mics), Ambient (more or the same mics), some people want play/pause sensors, complicated DSPs like the WH/WF which correlate ANC profile frequencies to your outside environment noises (gimmicky, but ok). But besides a good fit, we all want the best sound, regardless of taste and tuning, which will give you more headroom, less noise floor, more spatiality, more separation, larger frequency range (more deep bass, less treble roll off). And this is mainly obtained with a more power hungry crossover/amp. And of higher quality too. This is where (besides paying for the brand name) you get your higher price.
I rave about the Melomania Touch not because they are perfect (no ANC (want), no Qi (want), no sensors (I wouldn’t want these)) but because for 130€ you get, besides a very decent battery life, a very enjoyable sound quality, complete with width/depth/separation/accurate timbre/good timing and dynamics, all in a single DD. And a good app. Comparable to others only at twice the price.
So, with BTLEAudio/LC3 you’ll be able to retain/implement higher quality resolution and gain AND still being able to give you other features WHILE being able to cater for a decent battery life. (Oh, and while not jacking up the price too).
Edit: I almost forgot about hybrids, more drivers, DD+BA, more power needed. You probably can’t do this at 130€, but you can do it at 260€ (or less) and still give you decent battery, and more lower bass/less treble roll off, more resolution. More of all which we want. Tuning is taste or brand signature.