え、これ起動時のリアルモードとかプロテクトモードとかのダルいあれこれを廃止したバージョンをという話なんじゃないの？

Envisioning a Simplified Intel Architecture for the Future
https://www.intel.com/content/www/us/en/developer/articles/technical/envisioning-future-simplified-architecture.html

> Certain legacy modes have little utility in modern operating systems besides bootstrapping the CPU into the 64-bit mode. It is worth asking the question, “Could these seldom used elements of the architecture be removed to simplify a 64-bit mode-only architecture?”

たいした情報量ないな

https://cdrdv2.intel.com/v1/dl/getContent/776648

PDF の方にいろいろ書いてあるのか