Actually, it's a legit question, if phrased to ask why people think it's unfair, and really, none of the answers have been very good at all. The question can be broken down into several parts, and there is no good answer to any of them, IMO.
Does it enable unstoppable camping? No more than any other stage.
Does it enable any broken techniques? Not in any way.
Does it randomly reward a player for bad positioning? This is a hard one to answer, but ultimately, I think the answer is no. The rising lava floor and lava walls move slowly, and are easy to avoid and adjust to, so they aren't much of a problem. It is possible to find yourself near the safety pod without having done any work to get there, but as people have said plenty of times, the lava coming from the back is slow-moving, and one can jump over it.
I've never seen a problem with the level, for these reasons, and I fail to see why anyone could find fault with the level.