Easy. They write code. Code "works". Cool, ship it. Oh what's that? It has lots of bugs? How much money is it going to make us if we fix them? Eh, maybe

Easy. They write code. Code "works". Cool, ship it. Oh what's that? It has lots of bugs? How much money is it going to make us if we fix them? Eh, maybe we'll get to it. /s The real productivity win here is that you can hire a bunch of junior engineers out of university for "cheap" that "know" python. After all, why would you train a new hire in a different language for a few weeks or months when that would take a huge amount of time in startup-verse? /s? It's important to note that the largest push for things like type checking and access control in dynamically-typed, shared-mutable-everything languages are coming from the companies that built themselves quickly on these languages and now need to deal with scaling.