Ihor Radchenko writes:
See the attached. I am not sure if we really need the variable. AFAIU, acting natively was the default in the past for M-q with no region selection. Then, I "fixed" some bug report in 05ee1e6ee06db and introduced the bug herein.
You're right, I had not realised org-fill-element already acted natively. Your patch looks and tests good to me. -- Sébastien Miquel