I have read some literature on eastern philosophy, and some authors from that region, and there are many different viewpoints (same as in western philosophy). I probably agree with you on this topic, and I think there is some wisdom in "Spring. Summer, Fall..", but the impression the film left me with was a cynical view of this cycle you are referring to. I simply see the world differently. As the philosophical take of the film was for me very expressed in it (it rather stood out from the beginning, and was presented in a didactic way) , it played a big part in my response to the film as a whole.
I had read a lot on the film beforehand, and had expected something else. The visuals were beautiful at times, but were not as stunning as they appeared to many people. In places I found them a bit too repetitive and clichd, a bit exoticism for its own sake... And the direction by Ki-duk also wasn't to my liking, as I didn't think it subtle enough for this kind of story. There were far more ambiguities in Seom (2000), another film by him I've seen, and which I enjoyed more.