Building modern applications with purpose-built databases

Back in the 60s-70s, the mainframe was a predominant way of building applications. This lasted until the 80s, when client-server was introduced and significantly changed how applications were built. Apps started to become more distributed; however, the underlying data model was predominately structured, and the database was often a monolith. Then the internet arrived in the 90s, and as a result, three-tier application architecture emerged. Client and application code became more distributed, yet the underlying data model was still predominately structured, and the database remained a monolith. If you think about it, I would like to point out that people typically built applications against a single database for almost three decades. And that is an interesting data point because if you have been in the industry for a while, you often bump into folks whose mental model is, "Hey, I've been building apps for a long time,...