Yes, S4BIOS hasn't really been a thing for a long time -- once Windows supported S4OS (and didn't use S4BIOS even if it existed, since they quite reasonably did

Yes, S4BIOS hasn't really been a thing for a long time -- once Windows supported S4OS (and didn't use S4BIOS even if it existed, since they quite reasonably didn't trust BIOS authors to get it right) all the BIOS authors said "this seems like a useless feature" and stopped providing it. No idea about Intel Rapid Start. I don't really deal with that side of the system.