The days of just increasing frequency to reduce passive size are over long ago (two decades, maybe).
Increasing frequency by itself lowers efficiency and does that in a way that is nontrivial to compensate for.
The key is to concentrate your efforts in improving the efficiency. Then you can, at the same time, increase frequency and reduce the size. These goals work against each other so it's not easy.
Efficiency improvement have other obvious benefits as well - energy bill savings, CO2 emissions from energy usage. Traditionally, these have not been in the interests of the supply manufacturer, and still aren't, but miniaturization is finally driving efficiency higher as well. In many cases, it has also happened that heatsinking (cost of metal, if nothing else!), packaging, shipment volume, retail package size etc. are dominating costs compared to silicon or R&D. Large R&D volumes help. So a modern supply is often highly efficient, over 90% is nothing special now.