Given the relative simplicity of scaling down existing designs for lower current ratings, one would assume that Google is looking to achieve reduced heat dissip

Given the relative simplicity of scaling down existing designs for lower current ratings, one would assume that Google is looking to achieve reduced heat dissipation (<=> increased conversion efficiency) from existing designs at a given current rating, resulting in a higher kVA/m^3 value. There are few immediately obvious ways to attempt this, but all of them involve trade-offs in either cost, THD or operating flexibility. It'll be interesting to see what the full requirements are.