Sankhya was more interested in solving the hard problem of consciousness with which scientists are grappling now. The Sankhya philosophers nearly solved it by bringing in the Purusha whose intelligence is reflected in Prakriti. By assuming this they drew a gulf between the Purusha and Prakriti. This was the main error. This shifted the focus from a further understanding of Prakriti (which was Jada) to a withdrawl of sanction of the Purusha and a consequent dropping off of the bonds of Nature.
However in the meanwhile Sankhya, and certain other schools such as Vaisesika, nyaya, mimansa, later tantra, did try to solve the mystery of creation and in the process explored Nature, made their discoveries, developed science of healing, astronomy, physics and chemistry and their numerous applications in ancient India. Perhaps the ancient Indian Science was more developed than the Greeks at the corresponding timeline. The decline of ancient Indian Science came mainly due to the excessive stress on moksha and otherworldliness giving a lie to nature by calling it an illusion.
Christianity and the Church did not encourage Science. It was the result of the cult of Reason applied in the field of Science that helped its advance whereas in India Reason and everything else was directed much more towards exploring the spiritual realms. Hence the developing Science was left half way and subordinated to the otherworldly pursuits discarding the world as illusion. It is this theory of Illusionism that did most harm to the further development of the different fields in which India was rather ahead of the Western world.
Affectionately,
Alok Da