Yeah, but that's no advantage if the device you're making can't be made any smaller due to non-manufacturing constraints, which is the case for power electronic

Yeah, but that's no advantage if the device you're making can't be made any smaller due to non-manufacturing constraints, which is the case for power electronics, a lot of analog electronics, and also a suprising amount of digital electronics as well (where the whole device will fit in the spaces between the bond pads needed to connect the chip to anything else).