angrysoba
Philosophile
It is in no way restricted to inanimate objects. There is only one specific object (well actually 7 billion+) for which that pronoun is frowned upon by convention. That object is the human being. And the reason is that humans mistakenly think they are too special to be lumped in with everything else that exists.
It is not a mistake, after all who or what is doing the lumping? Humans! The fact that society conventionally separates humans from rocks is all that you need to know that humans get special treatment.
Humans get to eat in fancy restaurants, go to the gym, make and watch movies, vote, get admitted to hospitals and argue with each other on internet forums. Of course these are "fictions" of a kind as objectively you have no more value than a rock, but you would be a fool to declare that you wanted to be treated like one. That's the Golden Rule.