I'm asking about this question, which asks for examples where in hindsight a project would have done better if they had avoided overlooking an area of expertise.
I would expect answers to provide evidence (as requested) and therefore not be opinion based. Although the choice of evidence to present means this can never be purely objective, I would not want to see "purely objective" as a requirement for asking. This would require closing most of the existing questions.
I'd like to see discussion on this particular question: both whether it is primarily opinion based, and any ways it can be improved.