The subsidies would go only to a class of hybrid car that can't start its engine unless the batteries were 90%+ charged in the prior 48 hours and are now empty.

This imposes a lot of undesirable constraints on the PHEV architecture. Nobody should want to actually run a PHEV down to zero - even if the current designs allowed it, which they don't AFAIK (certainly my Clarity does not). And if you do run the battery too low, the relatively weak ICE it's usually paired with will have a really hard time making the car perform adequately. Clarity's implementation is known as "angry bees" for the disturbingly high-pitched sound the ICE makes when trying to go up hills or accelerate on low battery.

While in a general sense PHEVs may make economic sense, I'm looking forward to a pure EV for my next car. Adding all the ICE hardware and integration with the battery pack greatly increases the complexity of the vehicle and adds a lot of maintenance burden and failure points.