You're deluding yourself if you even try to defend one. Not only has there never been very good writing in a single game; no game has ever even managed, deliberately or even accidentally, to convey (on its own or within any length of series) any kind of compelling, well-told story.
You may have managed to boner any of your preferred D&D, or weeb, or testo-ball-clutching bullshit into something you cherish. Honestly, though, you'd be ashamed at trying to wrangle anyone else, other than your most trusted nerd-mate, into seeing it your way. (You probably don't have any other friends though...)
All those stories are garbage. They don't hold up to any kind of scrutiny within the context of the best literature and you know it. Games have always been shit at telling stories; it hasn't changed. Some games (especially those from our treasured past) were better at creating a world within which to imagine stories beyond that which were actually, lazily, barely written. That's the best you can hope for from a medium which doesn't even recognize games as a place to put their writing talents other than as a last resort.
That's what games are to writers: a last resort. There is no prestige here.
Until someone changes that...