I think you are massively overestimating the importance of the story of Half Life.
World building (to create tension and a creepy atmosphere) are much more important and also compact things, much more easily transportable and play a much larger role.
Since there will be hardly any plot-connections you are just not missing much …
Agreed, but I wasn't arguing it was. It's neither complex nor subtle. It is "story heavy" or rather story-driven, or rather "cinematic". This is a game where the story propels the gameplay. Not saying it's particularly good fiction, just that the fiction matters in the game. Notice how much of what I'm saying applies to Star Wars too, where -- also -- skipping a movie can be done but is not recommended ;)