I came here to say this but I see Chronos has beat me to it. Extraterrestrials would probably be so different than us that we would have a hard time determining if they were alive or not.
Eh. They’ll probably look like crabs.
Or just wear shower shoes. Though that makes cleaning your feet more of a challenge. But it beats a fall.
That’s just what they want you to think.
Cats are only “nice” because they’re small. If they were the size of tigers, they’d tear you apart.
I have heard that large cats can make good pets. As long as you feed them well. Roy Horn apparently failed to feed his pet tiger properly.
The faulty premise in the OP is that herbivores will be nonviolent, which is just bunk. Plenty of herbivorous animals are quite territorial and exhibit a lot of intra-specific violence. And it’s specifically territoriality and intra-specific xenophobia which leads to nuking yourself to death, not attacking other species. Never mind that herbivores can be quite brutal, not merciful.
Me, I’d rather never meet aliens who evolved from hippos.
Firstly, it doesn’t really help for the Fermi paradox, as we have no reason to think omnivores would be particularly rare.
Secondly, even the grouping of herbi- carni- omnivore might not make sense on another world. Photosynthesis might fit in in a different, or very indirect way.
Finally my own WAG is how aggressive a species is will be tied to group versus individual instincts. And I suspect that humans are quite close to the maximum aggression for an advanced species; we form tribes that fight each other. A more individualistic, or a more colony based species, will both be less prone to war than us.