Your still burning significant CPU resources and turning that RAM on (rather than power gating it) to run Electron apps in the backgrohnd, hence why it tanks battery life on laptops.
I don't know if they ever went live with their tablet design but I recall reading LKML emails several years ago using / improving movable memory code so they could easily hibernate or drop chunks of RAM, so their tablet wouldn't have to maintain refresh on 8 GB of RAM when they only needed 1.
Most operating systems have chosen a different tradeoff, reducing fresh reads from persistent storage, keeping files cached in RAM, which may work out to equivalent power savings.
