That's why the train example was bad. And not just because of short term reasons or emergencies, but because diesel is more efficient for low-speed, high-load setups. Diesel locomotives will eventually make way for hydrogen trains. The IAF needs full electric, not a mix.
And there is no shifting of goal-posts, merely the reader's understanding of the system. ACT by itself on a 4.5th gen airframe is not sufficient, that's why low level flight was always mentioned alongside it. But any 4th or 4.5th gen airframe without ACT is gong to be useless against 5th gen and higher regardless of other features. So it is still central to survivability.
And there is no shifting of goal-posts, merely the reader's understanding of the system. ACT by itself on a 4.5th gen airframe is not sufficient, that's why low level flight was always mentioned alongside it. But any 4th or 4.5th gen airframe without ACT is gong to be useless against 5th gen and higher regardless of other features. So it is still central to survivability.