The rationality is based on the specific aircraft. Size of the hull, and weight of the hatch are the two factors. I remember a CRJ-200 policy to eject the hatch while most larger are to remain inside.
Now, for myself flying as a passenger with knowledge of how the exit works. 6'4''/ 275lbs, I am going to remove that hatch flip it sideways and toss it clear of the aircraft in seconds.
A normal passenger or the possible 115 lb flight attendant would be better off laying it on the seat as directed.