Is that from other experts with a very close understanding of the specifics, or random people online?
What I find is you start with several viable approaches, pick one and go down the path enough to figure out the downsides. At which point you need to decide to backtrack or keep going. That’s the hard part not simply coming up with a seemingly simple solution.
Not "random people online", but I've got a few friends I think of as "terrifyingly smart", and one of their common characteristics is how they've all, in areas of expertise I've been investigating/researching/working in for weeks or months and which they have barely a passing interest in, quite obviously thought about a problem I'm describing and thought through a bunch of the obvious options, categorised them, and made conclusions about which avenues are workable and which should be discarded, and come up with either a workable solution or options I'd not even considered yet - all just in the course of a conversation over coffee...
(Somewhat frighteningly, two of those people are doing that at Facebook right now...)
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.
What I find is you start with several viable approaches, pick one and go down the path enough to figure out the downsides. At which point you need to decide to backtrack or keep going. That’s the hard part not simply coming up with a seemingly simple solution.