It'll be a good opportunity to see some nice hardware hacks, sure. But I'd guess serious miners don't really wanna deal with that shit and will just buy the miner-specific cards or use ASICs. This measure just raises the bar enough to make it a hassle.
Serious miners will go to great lengths to improve their efficiency by even a fraction of 1%. They will absolutely patch some drivers if it gets them better hashes/kwh (which it will or Nvidia wouldn't do this).
ethereum is asic-resistant, not asic-proof. It doesn't mean you can't make ASICs, just that ASICs are <10x as efficient as an equivalent-node GPU, vs millions of times more efficient for bitcoin/etc.
We’ll see a cottage industry of modders. Turning a $300 thing into a $600 thing should be a viable business.
Though I’ve seen some really sketchy mods before… can’t find it at the moment, but one involved taking a dremel to the chip to break an internal pad/link.