What is the benefit of having it in mongo in the first place, in this scenario?
If the devs want to use Mongo, it's their problem -- it shouldn't matter much to the analytics people, because they can just copy the data into a different database that fits their needs.
Certainly sometimes you are in a position where you just gotta take what other units in the org give you and deal with it.
But _someone_ in the org is hopefully in the position to be able to articulate why they are using mongo in the first place...
That's easier said than done when your database is over 10 TB big.
If you are really generating 10TB of data more than a few times a day, you can look into putting it in something like Kafka for real-time consumption by the analytics team instead of batch copying.
In general, you probably should have at least something in your stack which reads all changes from your DB, at the very least for backup reasons.
Automation here (in my case) is a net win on time.
It's sad that, for a backend DB, correctness can be trumped by marketing.