Putting into neutral isn't a necessity, any downshift in gears will increase the torque of the engine and thus decrease the maximum velocity. Even if you can't get it into neutral, getting it into 1st or 2nd will still get you slowed down to a more manageable speed.
The major failure of all automobile manufacturers is that they haven't implemented a fail safe mechanism in the event of engine failure at velocity. If they had it would literally be as simple as turning the engine off and the brakes deploying at a reasonable (IE not maximum) pressure.
The fact of the matter is that every vehicle except consumer automobiles fail safe from aeroplanes to tractor trailers (power failure leads to de-pressurizing of the air compressor and the brakes apply harder as the air level decreases). Toyota shouldn't be being hauled up, they all should be for risking civilian lives. IMO you accept certain risks when you pilot an aircraft, train, or transportation vehicle, however these are all typically far safer than the vehicles readily handed to consumers. That just is not right.