Reddit is an echo chamber, loudness does not equate to actual power.
On the contrary, loudness is an expression of confidence, which itself is rooted in power. That these people are so loud and unabashed about their irrational beliefs and ludicrous behavior all but confirms that power is at play here. Do you believe powerful people are modest and mild-mannered, or something?
Moreover, even if, for the sake of argument, we accept that loudness ≠ power, your mention of Reddit being an echo chamber is a red herring fallacy; it has nothing to do with whether this echo chamber is powerful, or represents the dominant (powerful) views of society.