The materials to make batteries aren't readily available in the quantities needed to add grid scale storage to all countries and replace all global ICE vehicles. Hydrogen is also ideal for countries like Japan where their grid isn't all connected (it's loads of small grids) and can't handle either the increased load from charging vehicles, or transport the energy from productive renewables areas to non productive renewables areas.
Like with most energy tech, we should be investing in it all so we have a diverse mix of solutions.