First, this looks really useful!

I noticed you are including this module directly in every instance of ActiveRecord::Base and ActiveModel::Model. I understand your intention for it to be a global extension to these, but as a user I'd personally feel much better about simply including it in the models that need it.

class Book < ApplicationRecord
  include HumanAttributeValues

  ...
end

Does that make sense?

By including in every instance of ActiveRecord/Model, you're effectively making the decision for me that the public API of every model should be augmented, even when it's not necessary.