The pins probably corroded as did the insides of the hinges. In effect they may be 'welded' together. Try some penetrant (not WD40) and let it soak for a day or so, then repeat. That may or may not help but it can't hurt. You can try tapping the pins out but you need a drift pin as wide as you can find but still smaller than the diameter of the hinge pin. Drift pin tools are like nail sets but have flat bottoms. Using something without a flat bottom can cause the hinge pin to mushroom and get even tighter.
Of course, heating may work but I wouldn't do that with the glass and gasket installed so try the penetrant and drift first.