I didn't write any of the 2mm on VRAM front guides for 3080 FE. I only did for the 3090, where I started with Thermalright Odyssey 1.5mm pads, but saw slow hotspot degradation over time, then switched to Gelid Extreme 1.5mm pads.
I did tell (with great hesitation as I could not believe a 3080 FE would take thicker pads than a 3090 FE!) some people many months ago about the "1.5mm on 3090 FE, 2mm on 3080 FE" but I was just "copying" the "reddit trend" from someone else's incorrect results --apparently the person who said 1.5mm pads were too thin either applied them wrong (or they moved when he flipped the card over--that happened to me once), OR he probably pressed them down with his fingers too much or messed up. VRAM junction temp is the hottest of any of the pads on the card, so any one stinker is the one that gets reported. A second person reported using 2mm Gelid Extremes also on a 80FE, I noticed his 16C hotspot delta instantly but he didn't care one bit.
Anyway, that lasted longer (Gelid Extreme 1.5mm on both Core VRAM And VRM's) but slowly the hotspot got worse (over 2 months, very slowly, just 2C but that was enough for me to notice), then I saw that the VRM pads were thicker than the VRAM pads (looking very closely at some stock FE pads after people took pictures), then I switched to 2mm on VRM's ONLY (Gelid Extremes) and everything is now stable.
The key to finding this out was someone mentioning having a 30C hotspot to core delta(!), yet their core was pasted perfectly. They took the card apart and there was a missing VRM pad on the left side, which gave me enough clues that "Core hotspot" reports the hottest section of BOTH the core AND the VRM's, similar to memory "Junction".