All it is is just a sucky situation. The game is a fangame with enough polish to at least compete with other games in the series. But not only that, it is a remake of an official game, not something 100% original. But the kicker is that they had M:SR in the works, another remake of Metroid 2. If AM2R had been allowed to stay on the market, for free, it is perfectly reasonable to argue it could have cut into the game's sales.
I'm just looking forward to when it comes out so I can compare and contrast them. AM2R is fucking amazing, so Mercury Steam really has their work cut out for them.