Constraints define good decisions. A new team member making a viable suggestion is very different from a random person tossing out a wild ass guess that happens to be right. The difference is the random commentator has no real way to judge how viable something is, and thus is simply tossing out ideas.
This can be right when things change over time and people still operate under their initial assumptions. Times change constrains change but on some teams assumptions and choices are not revisited.
These groups are not mutually exclusive, membership can only be assigned by a domain expert and is finally irrelevant if the other is right.