This has certainly been the conventional, general consensus take. All the more it's appreciated that Peter G. has made the effort to ask the questions of Doshu, Tada and others within Aikikai leadership to add necessary shades of gray to what has, unfortunately, often been a black-or-white discussion regarding the existence and acknowledgment of IP within, and influencing from the outside, the primary lineage of aikido.
Oh, sure. Nothing is ever going to be black and white in an organization as large and diverse as the Aikikai. Inside Japan, you have a large number of people with direct experience of O Sensei, who one might assume are going to prioritize (their interpretation of) what he taught over any guidance from the organization. Outside Japan, you have the practical impossibility of enforcing pretty much any central directive, combined with cultures that value direct experience over received wisdom.