It's something of a misconception that an RDBMS should be used for transactional workloads.
RDBMSs are table stores; in a sense if anything that's a model better suited for analytical than transactional not that that's really a fair conclusion either
If you have worked at large enterprises you should a few senior developers. Start talking to them. I'm a founder and I know a few other founders and that's how they all got started with the new startups/ideas.