In Dark Ages and Byzantine Europe mostly only commentaries on Aristotle's 'Organon' were widely available. Through shifting frontiers in Spain Islamic translations of more of his works became available, including his works like Physics, and On Generation & Corruption. These were at first condemned as heterodox and proscribed to read by the Church on penalty of excommunication, but went on to be incorporated by Aquinas and others into Catholic doctrine.
While Aristotle's wide curiosity and interest in everything certainly were a big improvement on the Dark Ages theology that had seen a lot of pre-Christian books burnt, there were also problems. Teleology was at the heart of his thought, the idea organisms are designed for and moving towards their purposes. Sponteneous generation of small animals from mud. His Metaphysics, which is thought to be lecture notes rather than written directly by Aristotle, is notoriously impenetrable, contains problematic ideas about essences and causation, and with Aquinas become core to Catholic doctrine. And many small errors that came from just not looking: an incorrect model of buoyancy; a belief men & women have different numbers of teeth. Aristotle was science-ish, but certainly not science. And his thought towered over the medieval world just like the ruins of the Colliseum did - a perpetual reminder that in a past Classical age people could do and think with skills long lost.
By the Italian Rennaissance the stature of Aristotle's thought and the high regard it was held in, had come to be a barrier rather than enabler. One of the defining qualities of that flowering of new knowledge, was superceding the Ancients, and proving new insights could be generated rather than just rediscovered. For instance by correcting Galen by referencing human rather than animal autopsies, and correcting Aristotle on buoyancy (though Descartes also got this wrong) and mechanics. This gave courage to question the big stuff: geocentrism, and the unfalsifiable claims in the Metaphysics. However some of his insights were not superceded until the 19th century, and a lot of his best thinking was not available or not understood in the medieval era.
See a good discussion here: Was Aristotle the first physicist?, article from the Guardian newspaper.