Yes, posters can post what they want within reason and everyone is entitled to their personal opinion, but it's good to try and be accurate and correct misconceptions, otherwise the ignorance and mistakes continue and no one learns any new truths.
For example, it's a common myth on here, that if we all set our sell price to $2 per share, that it would somehow prevent market makers from shorting the stock. Well, I don't think that our personally owned stocks can be shorted by anyone, other than us, the owners of the stock and yet that mythos is perpeatuated and usually goes uncorrected.
If you knew someone was wrong, wouldn't you want to politely help them and let them know what the truth is?