Let's take a typical APP built upon a typical tech stack, MERN = MongoDB, Express, React, and Node.
Let's suppose that my user base grows. I have decided to horizontally scale by distributing multiple containers of my backend Node server across multiple machines.
But if the MongoDB database is still just a monolith living on one machine, all of these parallely running Node instances will still have to query this one MongoDB instance, and so will have to queue?