All systems (126, 110, Disc and APS) required a substantial change for photofinishers in terms of processing and printing equipment. So, APS does not stand alone in that. What it stands alone in is the fact that the entire industry cooperated in its creation. All of the camera and film companies came out with this format at almost the same time, as they had foreknowledge. In the case of 110, 126 and Disc, they were closely guarded EK secrets.
At the time that APS was introduced, the models at EK predicted that digital would not become a viable amateur product for still photography until about 2020. IDK what the other companies thought, but the result indicates that they had somewhat similar thoughts as EK. In any event, that forecast gave the APS film format about 25 years of life! As it turns out these predictions were wrong.
I have said elsewhere that the forecast for film and paper in 2005 was that sales would decline by 30% in a year. In that year, in the first quarter the decline was 35%! This catastrophic decline affected Kodak, Ilford and Agfa in the public news. IDK about Fuji. That was the year that Agfa and Ilford had severe financial problems. I know that these problems were caused by a variety of factors, but the fact is that the overall market slumped catastrophically. My point being that all companies suffered from bad models and did so from as early as 1990. APS was caught in this hoorah.