Ah, yes, the Three Laws of Hypergrowth Startup Dynamics:
1) All systems that existed before you were unscaleable, unmaintainable nightmares
2) Any replacement system you proposed and worked hard on was extremely challenging, saved the business, and merits your promotion
Counterpoint: Java (Scala) microservices we’re an absolute nightmare for us at Twitter as we migrated off Ruby on Rails. Much of the complexity that Elon mentioned after he bought the company was from this architecture.