I think tonyedgecombe is pointing out that relying on 'group consensus' is not a golden bullet, as the consensus revealed preference of the national population conflicts with the consensus advice of subreddits' self-selected populations
Bit of a useless point then, isn't it? Of course group consensus of people who care about finance is going to be more useful to finance discussions than group consensus of the general population. And it's the former that we were discussing anyway.
Not to mention what they're describing isn't a group consensus on financial advice, it's just the stereotype of lowest common denominator behavior. It's like suggesting that there's a group consensus that playing the lotto is sound financial wisdom just because a large number of people do participate in it.
