I agree with you that choosing a boring stack and focusing on down to earth, understandable and pragmatic architectural principles offers good probabilities to

I agree with you that choosing a boring stack and focusing on down to earth, understandable and pragmatic architectural principles offers good probabilities to get a maintainable product. I would like to interject, though, that stack and architecture do not weigh equally on these probabilities. My observation has been that tech organizations fail when they loose their grip on pragmatism, regardless the stack. That doesn't mean that you should force the latest, unproven, JS framework on 200 engineers but if you have the culture for it one can easily succeed with react+JVM, elm+Haskell, etc. One interesting thing also is access to devs as each tech stack will attract different groups of the Dev society which will in turn affect your success chances.