The 787 was intended as a more electric aircraft, from the very start, even called the "7E7" during development. An electrical ECS requires special cabin air compressors with big motor drives and power electronics, but there was significant savings for the engines by removing bleed air. It makes sense as a system: Electrical main engine start, generator-optimized engines/APU, electrical cabin air compressors. But the trade criteria were the typical ones: weight, installation volume, total lifecycle cost, etc.
The choice of a lower cabin altitude _was_ a big deal though, and if I had to guess, is the main source of a more pleasant experience.
The main ECS vendors (Honeywell, Hamilton Sundstrand, and Liebherr) all have cabin air quality products, which have mostly gone without interest by the aircraft manufactures and the airlines.
Please to expand the acronyms?
https://www.boeing.com/commercial/aeromagazine/articles/qtr_...
The main points are increased efficiency and decreased maintenance costs.
Apparently to a similar degree. It seems that the European airlines are doing a good job (DHL, Lufthansa) as mentioned in the article about mandating this stuff.