Hi!
Other technical solutions can be found for keeping content apart when needed (e.g., separate dumps by entity types).
It's not only dumps, it's also searches, APIs, special pages, etc. Of course, everything can be solved with enough time and coding, but to me it looks like running a DB server with only one database and only one table - why not use separation that already comes for free with another instance? We still can reuse any code we like.