All of those are plausible but typically you have core teams built around product lines, teams that build shared components. maybe have infrastructure dev and devops too. maybe a database or datawarehouse team and data analytics/ stats team etc.. a cyber security team. all of these will have some team charter for where they fit into the business and there may or may not be shared resources technical and otherwise. These are typical in post market fit companies that are now “giant”. But yes, first you need the product, everything comes from there.