The stud in question is a tapered fit in the drag link, and may require considerable force to get it off. You might be able to do it with a pickle fork, or by hammering hard on the side of the drag link where the stud goes through (not on the stud itself - on the side of the part the stud goes through - it will often cause the stud to pop out). For hammering, it helps to have some tension on the stud, either with a pickle fork or puller. Then hit the side of the drag link briskly with a fairly heavy steel hammer. It needs to be a hard hammer but not so heavy that it twangs the whole steering assembly around. The idea is to deliver a sharp shock to the metal. A small hand sledge or a biggish ball peen hammer works.
However you do this, thread the nut loosely back on the stud, so that if and when it lets go it does not fly apart and cause injury or damage. It can really pop, and you don't want to lose any teeth, eyes, etc.