Darwinian evolutionists are extreme in their opposition to the idea that life originates elsewhere than Earth.
If I read your post correctly,
you’re asserting that darwinists are firm in their assertions that life has to originate on Earth?
I would say it’s the opposite. In order to “prove” evolution, they’d want to show that if it happened here, it could happen elsewhere, and ET life of any sort would show that.
Nevertheless, undifferentiated Evolutionists would like nothing better than to find some sort of extraterrestrial life if for no other reason than to drown the question of abiogenesis in a deluge of "interplanetary" speculation and "research."