PS#2. Hum, it's open source ! This is good, for it means anyone can run his own loom server. This makes decentralisation not necessary.
You can run your own loom server. But the assets you store on one server are still subject to a single point of failure.
So decentralisation is stilll 'neccesary' if you want to be protected against simply disappearing, cheating or defection of that node.