In addition breaking/finishing off a reasonable amount of champions, especially on your turn, it turns off Thought Plucker, makes Guilt Demon attack for 0, and knocks other champions off of their critical offense levels (like 6 offense for airborne champions)
This can actively incentivise losing your creatures as doing so gives you the artifact creature back
It all works and it's all awesome
Molten Collapse will have to compete with Terminate for Rakdos decks in Modern, but the versatility of Molten Collapse is no joke
Most of those cards got played with, damaged, lost, or tossed by parents who had no idea what theyd be worth decades later
How can you offer a more tempting target if you don't know what's in play