Decentralization brings an obvious benefit - if power is consumed near generation, you need less infrastructure to distribute it, thereby lowering costs. Once we start adding large numbers of EVs charging at home, our energy consumption will tilt more and more towards the home, making generation and consumption on the spot much more efficient and useful.
Another benefit of decentralization is grid resilience. Removing single points of failure by distributing them means that large scale power outages (while already infrequent) would become less frequent.