There's a difference between running at a pace that you can maintain for an hour and a half to two hours and running at a pace that you can't maintain for even a minute and half to two minutes. The old terminology, even if not totally descriptive, did a nice job of allowing us to know which sort of pace and/or effort we were talking about.
Beyond that, the idea that the bottom line is about lengthening your stride is deceptive. Sprinters have wonderfully long strides in most cases and generally couldn't compete at, say the mile, against mediocre high school runners because they get into too much oxygen debt, breathe too hard, become too anaerobic, become too aerobic,
aern't transporting enough oxygen, are transporting loads of oxygen...
I don't know how to describe why the sprinter has trouble racing longer distances now. But we know what happens to him and we know that he probably has great stride length until the effort of hard running for a long time constricts his stride length and frequency and we know he'd do better at the longer distance if he did more running at what we used to call aerobic paces, even if that was done as interval work.