I don't think so. I think higher ratings reflect better understanding of openings, better understanding of pawn structure, much better tactical skill, and better endgame technique to name just four attributes.
But I do think there is something in what you say. I think the endgame is an area of chess that is often overlooked by players lower down in rating (say, <1250). It is often crucial to decide whether to exchange that piece or this piece and often the decision is based on whether the endgame is favourable. But if you do not understand endgame technique, you don't know what to aim for; you don't know whether a particular exchange will be to your advantage or not. Strong players (say, > 2000) know this. They exchange and simplify the position knowing that it is simply a matter of technique and not making a silly error if they are to win that endgame.
I just played an embarrassing game up until the end. My opponent went on an aggressive attack and I missed a tactical move playing a bishop instead of a knight. After that, I was going down point by point and was down 7 at one part of the game. Then, as pieces came off the board, my opponent didn't know what to do and returned the mistakes in my favor. It got even, and I simply outplayed them in the endgame. This pattern seems to come up often. My opponents might get a significant lead and simply not know what to do with it.
So, I was wondering if the 1500-2000 range players are more adept to endgame technique. They don't go for tactical tricks early on or play aggressive. They simply outwait their opponents and then outwit them in the end.
I am always looking for an early trick or an early slip up for my opponent. Perhaps, I should just play solid until the middlegame. What do you think?