Why is this belief still being spouted? I'm an admittedly BK now and I want ranks. It's for me, it's not for pros. Competitive games need rankings. It tells you where you stand, where others stand and is also a good indicator if you're improving.
If you don't care about ranks, then it shouldn't matter whether you have a silver emblem near the playlist or a diamond one. Believe me, I get the tension at having to play ranked, but that's because we've become so coddled by other games and even the last few Halos where participation was all that matters. You see it all the time now. Gamers are just scared to play ranked because they don't want to be judged. It's why Spartan Rank, aka your time invested into the game is front and center. 
But who cares? It's a weekend/week playlist. After that it's gone and something else will come. Internal skill tracking will still function the same. I mean, you're still going to play the same or have the some ability whether it's social or ranked.