The writers the OSI Model wrote a specific blueprint, not an "observation of natural laws". When they said "session", they didn't mean the same things you conceive of. Instead, they meant a very specific problem of connecting dumb terminals to simplex links.
What you now call "sessions" is what OSI called "associations", and OSI defined them to be part of the "Application Layer".
I'm not sure you've even read the OSI Model. For example, the "Presentation Layer" is not defined to do the data format translation, but only to NEGOTIATE a common represenation. The actual data translation is still done in the Application.
This is the problem. People have not read and understood the entire model. They've not heard of "associations" and believe the OSI's use of "sessions" means anything they might call "session". They believe OSI was written as theory when it was not. They believe anything OSI terms they don't understand mean something else, mean some sort of timeless theory.
They are seduced by their own ignorance of the model.