> It's not clear that there are sufficient accessible deposits of lithium and other raw materials to meet the demands of electrification of everything via lithium batteries

Yes, it is clear. It’s one of the most abundant elements in the earth’s crust and is common in brines. Can also be extracted from seawater for less than current market spot prices.

Oh please, lithium "mining" might sound great, but there's a lot more to car batteries than lithium. Cobalt, which is essential for the longevity of a battery, is mostly mined by "artisinal miners" (2/3 of world's production). You know, poor people handling toxic substances to separate ores, and probably being paid less than this post cost to make. Not only that, most deposits are in geopolitically unstable regions / being explored by authoritarian regimes.

deposits in the earth != production capacity

if the increase in demand outpaces the increase in supply, you'll see a price squeeze, regardless of how much salt remains in the oceans

if someone goes and outlaws internal combustion engines, for instance, you may see demand increase quicker than supply can catch up

Clearly, but that’s a short term constraint, not a medium to long term constraint. The short term constraints on hydrogen are way worse, and hydrogen already has massive industrial demand that is being met virtually entirely by fossil hydrogen. If green hydrogen production was a slam dunk and we just needed storage, etc, then we’d already been using massive amounts of green hydrogen industrially instead of, like, 1%. (Note that in the US, 41% of electricity is clean.)

Construction is one space.

Another would be extreme cold environments. Most lithium battery packs I'm aware of in cars can be permanently damaged if they get too cold internally. In many cases there is a special heating element to prevent this by drawing just enough power to keep the battery in a safe temperature range. But I'm certain there are still edge cases.

The case everyone seems to ignore however; 'Developed' countries are just barely getting their act together with public charging infrastructure on the whole. Barely. What about all of the still Developing countries?

My stab-in-the-dark guess is that Toyota and Honda hope that at scale, Fuel cells will not be much more expensive than ICE vehicles. i.e. a Mirai and Camry if made in same numbers, would maybe be 1-2k away from each other in price. In that scenario, Hydrogen makes sense in a lot more places, even if it is not an ideal solution.

Hydrogen and BEV charging can easily go hand in hand, too, as hydrogen charging station is most profitable with on-site electrolyzers (which nicely bypass huge chunk of transport problems).

And while this cartridge is not super useful for cars (my understanding is that hydrogen charging been already done to high usability level) it does increase options for disconnected operations that presently have to use fossil fuels.