On the OP observation, there is a comment pointing out that “Site staff have clarified that escaped pets count as wild”, with a link to the thread with the clarification.
That decision seems right to me. An escaped pet is wild; a human didn’t put it where it is. It’s hard (maybe sometimes impossible?) to determine how long an escaped pet’s lifespan will be and what its chances of reproduction are, and observations like this on iNat could be a useful way to learn more about that. But even with a known fast death and no reproduction, it’s still (1) part of the ecosystem (it could be a vector for microbes, and its body will be consumed), and (2) subject to naturalists (at least amateur) wanting/needing to distinguish it from other wild organisms. It’s not always obvious what was a pet and what was not.