The reality is that we don't have enough electrical generation capacity to replace fossil fuel, not by a long way. Two things will happen over the next 10-15 years: ICE will be increasingly marginalised through taxation policy to indirectly fund the infrastructural investment required for alternative fuels, the net result will be far fewer cars on the road, they will become more expensive, and there will be hybrid autonomy / public car share transport schemes in major urban areas. There will likely be a mix of powertrain tech application; some H2, some EV, some PEM. Where you need range and high energy e.g. commercial trucks, rail etc, then PEM makes sense, for aero substituting kerosene with H2 makes sense, for small city cars, EV makes sense. The challenge is to move from brown hydrogen production to green, but that requires a massive shift to renewable electricity generation and nuclear. All of this before we consider the land grab issues around forecourt space that's required to service EV recharging and/or local H2 production.