I wouldn't call not playing an important/influential game a sin because I can freely choose to not pick up any piece of entertainment I don't want to play or finish for whatever arbitrary reason.
Half Life: I only played about half of the first game but I'm not interested in finishing a series that ends with a cliffhanger without any news about the last chapter.
The first Dues Ex: it probably has a great story but I'm not interested in the gameplay.
I've played all Bioware games but I only finished Mass Effect 2&3. They know how to craft a great story, an OK game, but not a good RPG.
The Wind Walker: I'll rectify soon enough.
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