RAM isn't much of a concern, relative to significantly increased needs for cache sizes and ROM sizes. Aarch64 very much loses out; Microcontrollers are resourc

RAM isn't much of a concern, relative to significantly increased needs for cache sizes and ROM sizes. Aarch64 very much loses out; Microcontrollers are resource-constrained, so they won't use it. High performance implementations (like Apple's M1) need to work around code density by making caches larger, or even having a microop cache; this all has transistor count cost, which imposes area cost, power cost and maximum clock cost.