I always felt that humanoid aliens were also a way to get the audience to more easily emotionally connect and treat them as characters. Its hard to portray a truly alien lifeforms with alien behavior like you would find in a speculative evolution fiction art book while also giving them a human understandable emotionally driven narrative and space age tech for the plot of a story. Its easier to relate to blue cat person than to the Blob I guess is my point.
I really like the comic Humanity Lost for its better representation of alien life in its story. The author really cares about that kind of world building ad im here for it really great stuff.
The amazingly innovative 1930s science fiction author Olaf Stapledon has an invasion from Mars in his epic history of the future of humanity and its various evolutionary stages, Last and First Men. The Martians are a gaseous life form that can come together to sort of form a jellylike mass. They originally think radio signals are Earth’s dominant form of life and everything else is their livestock. That feels much more believable to me in terms of how we would relate to each other.
