mannnnn dem dirty husseys....
There are two types
@bentwoody66 but the difference between the two is in the way the teeth are oriented not any real mechanical variation.
Brant is right that it is supposed to come out, in fact it should never have been inserted that deep, my instinct is someone hammered on it trying to get it out and drove it down into a tapered part of the steertube effectively wedging that mf'er in there stronger than a factory wedge.
Traditionally to remove a Hussey from the steer tube you "loosen" (which can mean an opposite thread that actually pulls the wedge up) the quill bolt but leave in place the secondary nut which holds the horizontal part of the stem in place. This gives you something to grab / work against while breaking the grease / grime seal and removing the vertical section from the steer tube.
In this instance, the horizontal section was obviously removed first, at which point the stem was loose but the holder didn't know it, then the stem vertical section was hammered down in there in an effort to remove it.
Bummer I know, my instinct in this instance is that it may be most effective to remove the steer tube from the fork crown and replace it with an identical steerer which would give you free range to get the base of the Hussey stem out and not ruin the fork in the process.