At the exact point where you don't need to learn another technology/framework and don't need to install yet another server side program (broker) anymore. It's

At the exact point where you don't need to learn another technology/framework and don't need to install yet another server side program (broker) anymore. It's another independent part that needs to be installed, configured and maintained. There are several "database as queue" approaches that work perfectly fine and none of them requires more than knowledge in your programming language of choice and basic SQL.