Convincing them to switch values may take a long time (or never), but in my experience you need to repeatedly stress the values you want the system built on, and give concrete examples of why whenever possible. Give practical reasons why simplicity is better (system stability, debugging, maintenance, etc).
But recognize that for some “smart” people this will be “boring”, and they will never do well. It reminds me of a manager I had ages ago who preferred C++ to Java because his C++ solutions required huge amounts of brain power for anyone to understand, where as the Java solutions could be understood even by dullards like me.