Not sure I understand your question. Are you asking whether it's good advice to play off beat openings because you are low rated? I say no.
You should think about the cause and effect of your observation. Maybe these players remain low rated because the play "weird" openings. I'm not suggesting you learn the reams of theory of the main lines, but you should learn to play sound moves rather than traps, tricks, or sidesteps that are designed to fool the opponent out of book.
I noticed that usually players rated less than around 1500-1600 will mostly play "unorthodox" openings , I have only seen a couple who play the mainlines of Spanish game or Sicilian instead steering the game into some weird positions . I am not sure if this is the advice that should apply to me ( Being only rated around 1600 otb ) , but I hate playing "weird" openings. In fact I think this is my weakness that I am not vey imaginative and intuitive enough when it comes to an opening that deviates early from book .