Most likely what they mean by that is an optimization of the system so that it runs better or low-end (i.e. cheap) devices (think: india, africa, china markets) as currently you need relatively high-end hardware for smooth operation.

"everybody" in this context means "large numbers of people who can't afford high-end hardware"

Google was talking about those optimization plans during last I/O, I believe.

You saw this already, right? https://news.ycombinator.com/item?id=6317614

For a minute, I thought you were trying to make a joke about how KitKats are meant to be broken apart.

Considering all the different flavors of kitkat in Japan, I would think it would become more fragmented, not less.