Linux was designed to run in home PCs, and we keep running it in supercomputers. It works just fine. Tools evolve.
Having separate tools for separate things makes sense when the things are different enough.
"Tools evolve" isn't a use case. So what's the use case where you need concurrent writes for a database that isn't client-server?
You can justify it as a migration strategy between a file and a service but you're just hammering in screws if you try to force Sqlite to be a multi-client database.
> If there are many client programs sending SQL to the same database over a network, then use a client/server database engine instead of SQLite[1].