Is there any benefits to a distributed computing architecture outside of cryptocurrencies? I was recently talking to a German start-up that was in an accelerator programme. They are building a product which is a distributed database that they are proposing will have efficiency benefits over companies which keep their data on their own centralized database. They talked about leveraging the computational capacity of different computers in the company to increase efficiency. From what I know about distributed computing, it is more inefficient than having a centralized architecture. Are there scenarios where it provides some efficiency benefits and is this being applied?
The only systems which benefit from being distributed are ones that display the property of being "embarrassingly parallel", or some approximation of it. Tasks which do not require a significant amount of data to be transmitted between operating systems, or those which don't require a significant amount of coordination fit this description well. Typically anything like a database is poorly suited to being distributed due to the need for overall consistency, which is very difficult to achieve across a distance. 

Bitcoin is the opposite of a distributed system at the node level, every participant in the system is expected to repeat the process of validation in perfect accuracy with the hundreds of thousands, or millions of previous attempts at synchronization that have happened before it. As the number of nodes increases, there is no change in the amount of computation done in either direction. 

Generally speaking anything claiming to improve efficiency by using a decentralized, or distributed network should be met with skepticism, simply because this is typically an uphill battle that is taken on for other reasons despite its inefficiency, not in an attempt to gain efficiency. To exemplify this, Bitcoin would be most efficient, most usable, and most reliable if it ran on a single server, but that would largely defeat the design brief of being trust-less.