Even if you're right about the connection you probably know very well that changing the environment in this game can take an excruciatingly long time, its very hard to pull off a continuously changing environment vs making more ''complicated rotations''. Raids have no static difficulty, their mechanics get easy (or boring obviously) over time, whilst the rotation does actually remain the same and could provide a ''challenge'' in times of drought for example.
That said I do not believe the two are as connected as you think they are. I also do not think ppl judge it by looking at these two aspects at the same time. I understand the idea behind it but in essence its ignorant of the collective vs the individual challenge.