There's thousands of helm charts available that allow you to deploy even the most complicated databases within a minute.
Deploying your own service is also very easy as long as you use one of the popular helm templates.
Helm is by no means perfect, but it's great when you set it up the way you want. For example I have full code completion for values.yaml by simply having "deployment" charts which bundle the application database(s) and application itself into a single helm chart.
You can't just "jump into" kubernetes like you can with many serverless platforms, but spending a week banging your head to possibly save hundreds of thousands in a real production environment is a no-brainer to me.