I've often seen the term applied to frames, but I didn't know it was also used about forks. I don't really like the terminology myself, as it implies that one thing is correct and everything else is incorrect. Whereas in truth there is a range of things, somewhere within which is your particular sweet spot, and (a) things not on that sweet spot but near to it are still quite good, and (b) your sweet spot may be quite different to mine. I don't see that a concept of 'correctness' really captures that.
BITD when frames were said to be suspension-corrected it was just intended to mean that it was ok to fit suspension to them. i.e., it was terminology designed for people who couldn't be bothered to think about the kind of questions that you're raising. In numbers, it generally meant that a 71 degree head angle was the accepted norm for sporty steering on a rigid mtb, and most makers hit on a 41cm a-c rigid fork as roughly approximating the sagged/active a-c of a 50-60mm travel suspension fork. So they took suspension-corrected to mean that the frame would give a 71 degree head angle if fitted with a 41cm a-c rigid fork.
A 100mm fork will generally have an a-c of c475m, so it will be around 445-450mm with sag and 375mm fully compressed. That's quite a big range and it means that the head angle at full compression is a lot steeper (6 degrees) than at rest and things can get dodgy with very steep angles. Obviously you only hit full compression for a split second, but say under hard cornering a 100mm fork is going to be quite a bit shorter than in the static sagged position. So my impression is that most makes have stuck with similar geometry for 100mm forks, i.e., still based on a 71/41 formula, but expressed as a 68 degree head angle. That is to say a frame that gives 71 degrees with a 410mm rigid will give c68 degrees with a 445mm rigid.
So the only use I can see for a 450mm rigid is if you either like a 68 degree head angle on a rigid bike anyway, or else your frame has a long top tube and very short stem. Such a short stem would give very fast steering unless it was combined with a slack head angle, so maybe that's why some people go for a slack angle on a modern rigid bike?
