I judge games by themselves, not by what effect they had on the industry. That being said, HL2 is good, but I prefer Bioshock: Infinite a lot more. You guys say HL2 had a real effect on you about story telling and gameplay? I say the same thing, but about Bioshock: Infinite. I completed that game 6 times, and now I'm just slowly going for all the achievements until DLC comes along. I just can't get enough of it. Everything about it to me wraps itself around so perfectly, in the words of Yahtzee, "like a bucket with 3 nice plump cherries". The perfect length, with everything that I expected it to do done right and more. An amazing story, VERY fun gameplay (specially on 1999 mode with no vending machines), a great setting, and relatable characters.
If you tell me to judge the games side by side, not by when they came out, not by what effect they had on the industry, or any other reason, I'd say Bioshock: Infinite in a heart beat. I just don't find Half Life as entertaining as people make it out to be. Infinite though, will stick with me for a very, very long time. One of the games that is very close to my heart.
I see some people saying Infinite will be forgotten but HL2 will be remembered. For me, it's vice versa. And I tried to get into HL in 3 different time periods. When I was little, when I was a teen, and just a few months ago. Still don't see the great appeal to it, so my vote is definitely for Infinite.