i have fpsVR
does that show VRAM?
What you are trying to do is very hard to do when you are going the other way. Games will allocate VRAM based on what you have available. It might show that you are using 23GB of Vram but that doesn't mean that if you played the same game on a card with 16GB that the game would perform worse.
If you are thinking of upgrading, Uncle Petey's advice on the previous page is good. Push up the settings in Virtual desktop and in the game to settings that you think makes it look good graphically. See what frame rate you are getting, see what FPSVR is telling you and look at the performance monitor in Virtual desktop and see what is happening with the Latency in the various sections, encoding, decoding, game and network.
Then wait until the reviews of new cards come out and decide if the performance of the card you are looking at will give you the desired performance in the games you are playing.
IF you upgrade your GPU every couple of years, I wouldn't worry too much about Vram. 16GB is going to be fine for the vast majority of games out there.
What I would be worried about is performance. IF you are going to paying a £1000+ make sure the performance you are going to be getting in the games you play is worth that massive outlay. Remember Ray Tracing and AI frame generation are the main focus of the 5xxx cards, not raster performance. So the big spend might not give you what you were expecting and you might be better off just getting a second hand 4090.