Everything I have seen written about these cards is that a repaste accomplishes nothing significant.
 
People say that the paste EVGA used is really thick and dry, they assume it is bad/cheap/whatever, they repaste, and the end result is pretty much the same.
 
So, this means that the paste EVGA used is thick and dry on purpose (to reduce pump-out-effect and increase thermal stability over the life of the product), but still performs good.
 
So, unless you hear otherwise, I wouldn't recommend changing the thermal paste.  The danger is: if you change it, you are going to use some thinner stuff which won't last as long (pump-out-effect), and so you will just be increasing the amount of future maintenance that you will need to do.

Can confirm, as I ended up having to do a repaste after finding out that the G10/G12 NZXT brackets don't fit for using an AiO water cooler on my 3090 FTW Ultra.

Using Thermal Grizzly Kryonaut didn't drop the temps at all.

You probably would see a nice improvement with liquid metal, but personally I'm not going to use it anymore after a CPU application dried out on me. Doubly so on the naked die of a GPU - that's a recipe for breaking off a chunk of the naked GPU die.

I tried repasting the first 3090 FTW3 Ultra I had(sent back in to EVGA for warranty replacement) with Thermal Grizzly Kryonaut and it didn't make any difference in temperatures.
 
A bit off topic, but I'm sure someone will ask about the card warranty replacement.  I had an unusual issue with the BIOS switch and support decided to replace the card because it could be a hardware issue.  When I flashed the 500 watt XOC BIOS fo the OC position, the "normal" position would show a 119% power limit in PX1 and MSI Afterburner even though that BIOS was never flashed.  Rebooting the PC or moving the card to another PC didn't resolve that issue.

 I used the Bykski water block as it was the only one I could get my hands on.  The block is actually great.  Problem I was having is the thermal pads.  After much debate I opted for the K5 Pro thermal paste for the back of the card.  It was a great move. However my vram on the back was getting much hotter then I wanted (Couldn't hold your hand  on the back plate.  Now I know it can handle quite a bit of heat, however I don't like the rest of the PCB soaking that temp 95-100C.
 
 I ended up going rogue and liquid cooling the rear plate with a 4 DIMM water block.  It's a massive water block, and I feel much better keeping that cool.  I also have a 2080 TI in the loop so I had to step up my radiator to a 60mm thick 480.  Yes, she's a big girl.   Running soft tube for now and making some small changes.  Mining I'm running 32C coolant temp. So I have both GPU's, CPU and vram in my loop.   Also running Antec Skeleton, so I have a totally open air system.  No, I just can't seem to leave my retro case. Even though I had to cut a section out to shoe horn the 3090 in :)