In that image you can see that FG is only for 40 Series, and only since DLSS 3 and forward.
Ray Reconstruction, which is what we are talking (and excited) about, will be included for all RTX cards, since DLSS 3.5 and forward.
Probably it will be available as a spare setting to be enabled/disabled, but maybe with the need of using DLSS, or DLAA too.