You can run ICE cars on LPG (propane + butane, would probably work on pure propane as well), with minor (<1000$) modification in the fuel injection system and fitting a proper tank.

This could make millions of older cars cleaner, also in the developing world. LPG is already cleaner, would benefit the developing world, and ICE engines can be produced without needing exotic materials, can be recycled 100% by smelting, are a proven, well known, durable technology, unlike lithium batteries (which are also proven, but recycling and exotic materials are problematic), and are and will be a popular technology in the developing world for a long time.

Also it would allow for cheaper and cleaner cars in the developed world, where not everybody can afford the electric dream many here are living.

It would also be somewhat suitable for long haul and heavy machinery, but most likely in a hybrid drivertrain setup.

Also it would solve the big issue of the German home heating and industry: how to stove away the sun and wind from the summer to the winter, when in the windless dark days nowadays coal is burnt, as battery of hydro storage cannot be scaled beyond a few days capacity at extremes.

There is already built, or cheap technology to gas powered solutions, no need to transition to new technology hastily. This would give runway to the green transition, as it could be net zero carbon footprint solution with less disturbance to the existing solutions.