It's the opposite. Any decent programmer can make a nicely architectured MVP. It is maintaining the code, refactoring it and implementing new feature requests not envisioned by the original programmers that takes real skill.
Stupid analogy time: Building a shiny, new house; easy. Retrofitting a 300 year old house with 1000gb ethernet wiring everywhere, while keeping the original character of the house and with minimal disruption to its inhabitants; HARD.