[nonameiguess]

This is a nice perspective from the developer of a single application, but as a platform developer, I'm usually dealing with using IaC tooling to set up multi-tenant environments. I can't just deploy one database because there may be 50 different teams working on 50 different sets of problems, some of them basic research, some of them products, some of them purely exploratory, and there are often legal restrictions on who is even supposed to be able to make a network connection to a particular database, so simply using roles and users built into the DBMS engine itself isn't good enough to achieve the required separation, not to mention they need to be encrypted at rest with different keys. This often needs to be done across separate accounts within the same cloud provider for budgeting and accounting purposes as well, so they couldn't just share a resource even if it was otherwise okay for them to potentially step on each other's work.