I don't know. Seems sloppy on Nvidia's part. I don't think they were planning on a mining explosion when their cards released - particularly during design/manufacture.
Seems like just a way to pad profits slightly. And a real shame.
Having tested and reviewed previous Founders Edition cards, I sometimes wonder if Nvidia is just trying to play it a little safe so as not to irritate its AIB partners. All of the AIBs have had better cooling solutions for YEARS. I was actually really hopeful with the 30-series FE cards (before testing), because it looked like they would be better at cooling.
With cards in hand, however, while they're quiet and run well for gaming, the backs of the cards still get very hot on the 3080 and 3090. Maybe not as hot as the 2080 Ti and 2080 Super, but close enough. This should have absolutely been addressed with the 3090, since Nvidia knew it would have GDDR6X on both sides of the PCB and that the back would get much hotter. I think it ended up going for a "cool" look -- which I actually do like -- over better cooling.
Fundamentally, it's very simple to put on better thermal pads and have more contact between the memory and heatsink. Nvidia should have done this on the 3090 and 3080. Even without mining, the VRAM temps are higher than normal and dealing with that rather than reducing the memory clocks would have been the right approach. It's obvious from the way the FE cards behave (GPU temps stay low, VRAM hits 110C, fan speeds go from 40% to 100% in an attempt to keep the memory cool) that the engineers recognized what was happening and built in a "failsafe" of sorts in the firmware. Possibly it was too late for the first batch of cards.
Hopefully the future updates (3080 Ti or whatever) tweak the design just a bit. We're talking about pads that probably would cost Nvidia $1 per card extra. On a $300 card, that might be a problem, but on a $700 or $1500 card? It's nothing.