There are two answers to this question. One of them is lame. The other is educational, but I don't consider it as correct as the first one.
The lame answer is that yes, the card changed. This is because the rules back then were different, which means that understanding what a card does is different. That is, trivially, every card changed when the rules did.
If you don't buy this answer you can also consider the fact of the special case: that the original magic rules, and card texts, just weren't well-defined. Asking if behaviour changed, when behaviour could in many cases only be a matter of Rules-As-Intended not embodied in any discernible object (in objective reality), itself becomes not a matter of answering something definitively but a matter of discerning an opinion held in the past. So Old-Balance did 'something', which exists and is basically unknowable. Balance does a thing, and if that thing equals what Old-Balance did seems to be just like asking if a value is equal to the undefined type - useful to consider that 'false' on principal.
The esoteric answer is that there is a difference between discarding "until" your possessions satisfy a property P(x) and choosing possessions satisfying P(x) and discarding the rest. The second case clearly involves no sequence of actions. The first case might possibly have been a sequence of actions. As the order of things matters, the two cards are different.