It has also occurred to me that what I was calling a "profile" is almost what one could call a "session".
I might want to spin up a profile/session (perhaps directly from the machine list or even duplicated from an existing profile), whether it be for that long game of MULE or something else, and if save states are supported, exiting the emulation would persist the save state automatically. When I am done with that profile/session, I would then delete it. This does not preclude more permanent profiles.
I know nothing about RetroArch, but I strongly suspect it is targeted at a different type of user.