Earlier quoted context omitted.
The fiction is to believe that 'a legal construct (perhaps multilayered) that groups ownership of real assets and/or obligations of real people' is an entity.
You're basically saying that contracts are fictional. Try entering into a contract, then behaving as if it's fictional by ignoring your responsibilities in the contract, and you will quickly find out how real they are.
Nope (although, that may be true, in some sense), I am not saying that. I am saying the thing many refer to as an 'entity', as in, 'the corporate entity', is a fictional thing. It has no real, inherent or independent physical existence apart from the people that choose to represent it.