Some time ago I was talking to some bank software engineers and they loved mongodb because the schemaless nature let them avoid all the red tape which DBAs had created within the organization. Mongodb solves an organizational failure more than anything else.
I deal with text+discrete data. On the one hand this falls well into a document structure, on the other hand it wasn’t clear what exactly was offered on top of what we get from our current setup of elastic+rdbms (we are ok with data duplication and records are ~immutable).
Honestly I don’t have a clear recollection. Their point was to impress on us broad adoption so big names were dropped. This was in the context of Mongo Atlas, their cloud based solution, and how it is being used in heavily regulated/strong privacy environments.