The way this seems to work currently is, the only way to make it ‘auto save’ on exit is to exit via the menu.
However, I tested this feature when I first upgraded to 1.5.0, and it seemed to work even when using hotkey shortcuts to shutdown, which is what is much more convenient.
However, upon closer examination, it only auto saves the first time you exit - meaning, every time you start up the game, thinking you’re going to be right where you left off, you’re actually going to be loading the save state that was saved the first time you exited RetroArch.
So, I just wanted to bring this to the attention to the devs, as it seems like someone was trying to make it work even without having to enter the menu to shutdown RetroArch first.
Also, I haven’t upgraded to the latest version of RetroArch to see if this issue has been fixed or not. I searched the forum and it hasn’t been brought up.