What makes the BoP explosion stand out is that it explodes in a unique fashion. It's not a model with an explosion graphic slapped over it. The model is blown up in sections, bit by bit. It's actually a pretty slow destruction, made to milk the visceral impact, the immense high in TUC as torpedo after torpedo hammered the damned thing at the end of a one-sided battle. It's extremely distinctive. And when it was first shown in theaters in 1991, the audience cheered. I got a tingle of excitement for years rewatching that. It was perfectly done and intentionally created to have this effect on people.
Then, the next film uses the exact same shot and it stands out (to fans) because of what I described above. It wasn't just another ship being blown up, it was the emotional climax of the previous film. Because of this, what should have been a fist pumping climax in GEN just deflated.
GEN not only reused the explosion, but they tried to rip off the entire scene, right from the moment Kirk/Riker says, "Fire!" You get the hushed silence, the torpedo slowly heading toward the BoP, closeups on the Klingons as they realize they're dead, then... BOOM! Klingons go flying all over the place, then the recycled explosion.
The trouble was the GEN scene didn't have the same impact at the TUC scene for the reasons you described.