I tend to agree, while some players DO tend to get really unlucky, top players somehow all manage to get to high elo. Probably elo-hell mentality comes from players not being able to grasp the overal "strategy" of game, where many factors should be taken into account of loss/victory and the player himself might not realise, that the mistakes he did affect the game more than he thinks.
For example a "elo hell" player, who usually plays carries and gets good k/d ratio, thinks that his team sux as they feed and such, while a high elo player would do something to prevent that and "optimise" the game.
Im no high elo player, but i believe i did happen to get into "elo hell". Basicaly i had 1400~ rating, then got into massive losing streak due to teammates just TOTALLY FEEDING, feeding so incredibly that its hard to believe. If not feeders, then i would get leavers, i think at some point i had several games in row where one of our team left or didnt even get to game to make it 4v5.
Now i almost managed to get back to my previous elo due to huge win streak, but i can imagine some players get stuck in the "elo hell" alot worse than me.