(First time here, I hope I'm doing it right ;) )
It's about the original Beauty question.
Why is it tagged as opinion based?
There are several definitions of beauty, e.g. at Merriam Webster, that sound alike:
the quality or aggregate of qualities in a person or thing that gives pleasure to the senses or pleasurably exalts the mind or spirit
The Question asked is, in my opinion, NOT "Is xyz beautiful?", which clearly is opinion based, but "Can only humanoid things be beautiful" which is clearly not opinion based, because there are definitions of beauty. In case of human beings there are even mathematical formulae (Golden Cut, Legs to Body ration) that define beauty (In the phi of the beholder).