Food for thought: since Chia's farming is a one time event, it may make sense to start building high density write once ROMs again.
You can buy 1TB microsd cards these days. That's far more volumetric density than a hard drive platter. IIUC part of why that's achievable is because these days flash chips have almost 200 layers on a single die; stacked dies have even more layers.
They're about an order of magnitude more expensive than hard drives. But maybe that can be reduced if write once.
@pete It's like every environmentally friendly solution: you just hide the direct environmental damage from sight and people can feel good about themselves.
Bitcoin doesn't kowtow to their feel-good needs and pushes the truth in their face, so they hate it.
...and yes, I think the development of custom storage just for Chia would be a ridiculous joke in terms of environmental friendliness. Trading off energy consumption for energy consumption in disguise, plus a lot of e-waste, would not be a good thing.