More likely, your "type B" programmer will build a half-assed MVP with 20% of the initial features that will break every 5 seconds and thus the "million dollars

More likely, your "type B" programmer will build a half-assed MVP with 20% of the initial features that will break every 5 seconds and thus the "million dollars paying startup" will lose their customers to the saner competition. I will also very much question your visionaries/maintenance distinction. Many dynamic languages today are influenced by technology developed in academia. This is because the "type B coder" you are speaking of lacks the theoretical foundation to build sound abstractions that are proven to not break. I would describe myself very much as a "type B" personality - I'm completely disorganized, messy and lazy. I've event gotten into (physical) fights with flatmates over this. And precisely because of this, I'm choosing technology that takes away all the rigid bookkeeping and context switching that is needed when writing anything more complex than a basic Bootstrap/Angular/whatever bullshit CRUD app. This is because refactoring is a lot harder in a language without structure. I would never dare rip out the base data structures and replace them with something completely different in a project with more than 2kloc in a language without types. While in a logically sound language I do that daily and don't even care - a perfect fit for my "type B" personality.