It could be and probably is a combination of many factors.
Simple one is political opportunism, that is as opposition, you oppose anything that you can get away with. They perhaps see long term gain in painting Modi as anti-farmer and pro-rich.
Next, if you look at history of such people, this dynasty considers itself the rulers and in a sense owners of India. Thus, what they want is a backward society that considers them their mai-baap so to speak. A sort of feudal system, where the farmer is entirely dependent on the zamindaar.
They don't want progress beyond a level. They'd wish for most people to be under- if not un-educated, thus enabling these mai-baaps to fool them easily on the basis of caste, religion etc.
Another angle is their foreign allegiance, which would want India to be developed enough to be a huge market and have enough factories for their business to exploit cheap labbour, but not so developed that it becomes a challenge for them.
I am sure there are many more factors, but that's just from the top of my head.
I am sure they'd be a few AAP supporters who would have jumped ship from being Congi fanboyz. There were a couple prominent ones, Prometheus and that Guynextdoor fellow if I recall accurately.
You could tag them here to get their views.