I will just point out that not all "iai" styles are conceived or practiced in the same way, not even close. There are also "traditional swordsmanship" styles that contain iai within their curricula. Not everything is public domain, so opinions of what constitutes this or that will vary based on available information.
Of course... but in the end there is still the question of whether a particular means of "striking" with a sword will actually cut effectively and do so without damaging the blade. The answer to that question doesn't care much about who is doing it. Just how. And it's quite reproducible. You know, physics and all that.