Why are polymorphic associations not supported by inverse_of?

Question

From Rails Guide:

There are a few limitations to inverse_of support:

• They do not work with :through associations.
• They do not work with polymorphic associations.
• They do not work with :as associations.
• For belongs_to associations, has_many inverse associations are ignored.

Answer 1

This is no longer true. The inverse_of is supported by through, polymorphic and belongs_to and has_many associations. The automatic detection however is not supported for through and associations which define foreign_key.

https://guides.rubyonrails.org/association_basics.html#bi-directional-associations