The key benefit of fiber optics communication is its superior bandwidth (or throughput). A large bandwidth means more customers served. A quick comparison between fiber optics comm vs LEO (low earth orbit) SAT comm can be referenced here.

BTW, LEO SAT comm is also routed to the general telecomm network, as a part of alternative comm path. Once telecomm network is down, LEO SAT comm becomes useless in that no info would be routed to LEO SAT. How good is it if LEO SAT communicates with your SAT receiver with only preambles just for the sake of connection?