As the chart in the video shows,

DLSS 2 adds fps improvement to 2000, 3000, 4000 Nvidia cards in MSFS.

DLSS 3 adds frame generation to 4000 series cards only in MSFS.

DLSS 3.5 will add ray reconstruction to 2000, 3000, and 4000 series Nvidia  cards.

I suppose how much you like these technologies depend on whether you are gpu or cpu limited, or both , or neither. And  also your like and dislikes of the strengths and weaknesses of the changes which these technologies make to the sim's  images.

For me DLSS 2 was an enormous improvement and DLSS 3 (FG) was also. Perhaps because I was pushing a fairly large number of pixels. FG does double the frame rate, that's what FG does. But half the frames are produced artificially and lag comes in. But still, I always use FG and love it.

In VR, there's something kinda sort of like FG called Motion Reprojection. It's in the MSFS VR options. FG does not work in VR. But MR does work in VR. Both FG (2D) and MR (VR) are enormously beneficial to me.

It is possible (so they say) to "side load" FG into VR. I have not tried and unfamiliar with the details. Others are already doing this.

Gamers Nexus on Ray Reconstruction (earlier this morning):

 

 

 

 

It looks like from video that maybe DLSS 3.5 (ray retracing) (available on 2000, 3000, 4000 may only yield 8% increase fps, depending on the game or sim).

DLSS 3.0 (Frame Generation) (only available on 4000 Nvidia) increases fps enormously in the video charts. I'm seeing double fps just about everywhere in MSFS when FG is turned ON in MSFS options (RTX 4070).

Basic 4070 cards suggested retail price decreased $50 3 days ago from $600 to $550. Also on Amazon, etc. Draws fewer watts than 3070, and can be as small as 40mm wide (1 and a half slots).