Unless it is something in the silicon it won't matter. Miners are and have been writing their own drivers and bios for a while now. They will still prefer a card that has resale value.
Exactly. Mining operations don't want cards that will be useless when the mining market crashes. They want something they can resell to recoup a big chunk of their investment once mining becomes unprofitable. And with money on the line, I find it hard to believe they won't quickly find a way to mod the drivers to circumvent this software restriction.
And as the article points out, even if miners were buying the mining cards, that's still taking away from chips that could have been going into normal cards, so it's unlikely to help availability. When this latest mining rush inevitably ends, those cards won't be capable of acting as normal cards, so that's ultimately less graphics cards on the second-hand market. That makes selling such cards attractive to Nvidia in the long run, as they won't need to compete with them for sales in the future, but not really useful to anyone else.
Nvidia explained in today's announcement: "RTX 3060 software drivers are designed to detect specific attributes of the Ethereum cryptocurrency mining algorithm, and limit the hash rate, or cryptocurrency mining efficiency, by around 50 percent."
Also, that makes it sound like they are specifically targeting Ethereum with the drivers, but not really other cryptocurrencies. So even without driver workarounds, the cards may mine other currencies at full performance, and perhaps even Ethereum if the algorithms are adjusted. If, on the other hand, it is a more general detection routine targeting many mining algorithms, that makes me wonder if there could end up being false-positive detections that could cripple performance in certain games and applications.
If you don't want miners using GPGPU for mining, the only real way is to give them something faster and more power-efficient to use to make GPUs non-competitive just like ASIC miners did for BTC.
Of course, just as a lot of newer cryptocurrencies were designed to be "ASIC resistant" to ensure they don't require specialized hardware to mine, the same might happen there if those other options gained a significant advantage.