ELO Hell Is The Reason People Are Stuck?

So two weeks ago, I have made a few friends in game that are in bronze or silver. All of them believes that they are better than the people in their elo and deserves gold or plat, and since I have higher ranks, a few of them challenged me to 1vs1 to prove that they deserve to be higher and only stuck in bronze/silver because of elo hell. Of course I won all the 1vs1 pretty easily but they still claim that they were able to keep up in lane with me and deserves higher rank. So do most League of Legends player still believes in elo hell? I have seen a few player who were definitely better than their elo while i was on my smurf. But I thought that players eventually end up in the elo where they belong. So what are your opinions on this matter? Are people stuck because of elo hell?