[AgloeDreams]

Exactly, they were originally acting extremely forward thinking. The one thing they simply did not see coming is the mid-2000's mobile tech revolution. The cost of lithium batteries fell like a rock to where they are today (due to smartphones, etc) and that was simply unforeseeable 20 years ago. What Toyota needs now is a single skateboard platform for both BEV and FCEV and then to simply build the FC models with a dummy pack structure and keep the entire rest of the design the same.

[WorldMaker]

To keep weight/handling similar they could probably even fill it with as many batteries as they can subtracting only the full weight of a filled fuel cell (ie, it may not be so much of a "dummy" pack). That might keep HFC EVs in line to be the last surviving PHEV model as ICE retires, which would keep/permanently enshrine Toyota's (Prius) spot in the PHEV hall of fame.