What is the reason for older jets and turbo props choosing electric driven gyros vs vacuum driven gyros?
Electric gyroscopic systems provide redundancy to vacuum powered instruments.
"Older" (and modern) jets and turboprops are required to fly in all kinds of weather, including iceing conditions which may interfere with some vacuum driven systems.
The likelihood of complete electrical failure in a multi-engine aircraft is extremely low, and electric instruments can still function for some time on batteries.
Interestingly, vacuum systems came along first, some driven by simple venturi tunes on the outside of the plane, with only the magnetos providing spark for the engine.