Yes, this game will die. Eventually. Anytime soon? No. I've seen MMO games in far worse shape which are still going years later. GW2 is not the top MMO, but MMOs overall are in decline and among the pack GW2 still has a very strong position.
You may not like LW releases but please dont act as they dont constitute new content. That is pure fallacy. In fact, LW patches could serve as a model genre-wide definition of new content. Yeah, I would also like to get a new big expansion. But the fact that we don't get one does not mean that GW2 lacks new content.
If you are worried that GW2 will die I have a news flash for you. You will die as well. Does that mean you can't enjoy your life for now? If you like playing GW2, keep doing so and just enjoy it. If not, move ahead to something else.