[Dire]

HL2 is getting to be pretty dated, so most people you're going to find playing it online have been playing it for a rather long time. And most of the bad players will have already become frustrated/quit. No more fish in the sea.

Same thing happened for me with Halo 2 (which was released the same time as Half Life 2). When it just came out, I used to play it quite alot and did very well at it. When I decided to load it up again a couple of months ago, I was getting beat down so bad I was convinced everybody else must be cheating. Just turns out that the the majority of those left playing eat/slept/dreamed the game.