I think that ship sailed a couple years ago. In hindsight, maybe they should have acted to prevent ASIC mining and kept things at the CPU/GPU level. That would have maintained greater decentralization, I would think. But even with GPU mining we face these kinds of situations. When I was GPU mining X11 I recall how someone came up with a pretty good refinement that boosted hashrate. They sold it to one miner, but it ended up leaking to everyone pretty quickly, robbing them of any further profit.

A software-based innovation would probably be worthless to patent (piracy would be rampant), but one could easily envision inventors encoding their innovations in GPU or motherboard hardware and creating the same scenario: Only those who buy the patentees' hardware could survive.

But killing ASIC mining now would be virtually impossible. For one, it would render hundreds of millions of dollars worth of mining hardware worthless - so 100% of the existing bitcoin mining industry would be dead set against it.