When it comes to gaming no one is a better judge of your own tastes and preferences than you. Sometimes, particularly on the internet, that truth can escape us, and we start believing what others want us to believe rather than what we know to be true for ourselves. I think this is normal human behavior when you are in an environment filled with other people. Online this is amplified because there is a kind of natural selection at work involving the rhetoric of preferences, where the best crafted arguments, even if they are untrue in the end, dominate the conversation. A lot of people give in to this, and cede their own point of view in the process.
But when it comes to taste, these debates can grow rather silly. Often what it amounts to is a person having a gut response to a game, mechanic or style of play, then trying to explain why that gut response is there. Another person might step in and debate the reasons the person has laid out. This doesn't make the gut reaction wrong, it makes the explanation faulty or incomplete, and those are two very different things. Other times the explanation is perfectly fine, but specious argumentation wins the argument/thread.
I also see instances where a dominant strain of thought becomes imbedded. It has simply been said for so long people assume it to be true, or those who disagree have lost the argument too many times (again even if they are not wrong in the end). Schools of thought are fine. They can help people navigate the sea of ideas present in the hobby. But militancy about ideas isn't good. I have succumbed to this myself and have stopped because I see it as being highly unproductive and a sign of insecurity in one's own beliefs.
I think there is a place for discussion about gaming, both in real life and online. I myself participate in a number of gaming forums, and these have helped expose me to ideas and concepts I might not otherwise have known about. This is all good. But it is a double-edged sword, leading to cliques and attempts to find the one-true way of gaming. While this is sometimes the result of a single skilled debater or forceful personality, the true fault lies with those who follow along. No one can force you to believe something. No one can force you to play a particular way. If you do so at the insistence of a stranger online or a gaming friend at the table, then you have only yourself to blame. So pull back for a moment, think and don't just accept what is presented because it sounds good. If it doesn't ring true, do not adopt it.
This applies to everything from play style to the way you GM. I give a lot of GM advice here on this very page. My hope is people find it helpful and that my experiences at the table have something to offer others. However I wouldn't want anyone to adopt my ideas if they don't feel right or contradict something they believe. So by all means take what is useful for your game from a variety of sources, but remember to think for yourself.