That depends on where you are located. In California I don't think that "employment at will" applies and since the majority of Google's employees are in California they have the option. Though I can't see them ganging up to form a union.
I remember hearing long ago how adding pumice to concrete made it better able to resist water damage. Supposedly that was the reason that aqueducts and other Roman structures exposed to water survived for centuries. I don't suppose pumice has the CO2 benefits but it's also something just needs to be mined and not made.
Though I doubt either one is available in the quantities needed to be really useful. Also wasn't there some report on us running out of the sand needed for concrete at our current rate of use?
Supply can be an issue, but there are other factors that come into play that I've heard about. Apparently DRAM had a rather large increase in price recently which is creating an issue for board manufacturers.
Then there is the issue that AMD/Nvidia remember what happened last time there was a big increase in the price of crypto currencies and then a huge drop off. So they are rightly fearful of such a thing happening this time because they have to place orders for more GPU chips months in advance. So they would have to feel confident that the current high demand for cards will still be there six months from now in order to place a larger order for chips from TSMC/Global Foundries. I can't see any reason for them to be that confident.
A morsel of genuine history is a thing so rare as to be always valuable. -- Thomas Jefferson