Though I suspect that might just be the whole 'video games are a relatively newish form of media' as compared to the modern comic.
I agree a lot with that statement. I think video games have to age in order to be more accepted. As far as I can tell, the console video games got their huge boom during the baby boomer's children's generation, and now that most us baby-boomers' babies are turning into adults ourselves the market is changing. The media LOVES to present video games as "nerd stuff" and "only something the uncool dweebs do", but that is slowly changing as video games are becoming more and more successful, which I speculate is due (at least in part) to the first real gaming generation turning into adults.
If you look back to early voice-acting in video-games, they were usually dismal affairs, with God-awful voice-acting and people too embarrassed to be known they had "stooped" to such a low-level. Look back at some video games like Symphony of the Night and Resident Evil, and you can see some examples of bad voice-acting (although some of them ARE trying their damnedest) . True that exceptions DID exist (Legacy of Kain and Starcontrol 2 are great examples), but they were just that--exceptions. Listen to the original Resident Evil and its REmake and you can see the world of difference in the voice-actors, as video games have become more popular and it isn't so stigmatized. Popular comedians like Dave Chapelle and celebrities like Mila Kunis admit they play stuff like World of Warcraft--despite the media's unfavorable portrayal.
E-sports is still a growing community, too. In countries like Korea, there are Starcraft II celebrities who are widely-hailed, and even have entire events dedicated to watching them play on a giant screen. Hell there are countries (like Korea) who PAY and ENDORSE people to play SCII and represent their country. Even here in the U.S., there are things like the NASL (North American Star League) which offers a membership to view SC2 matches and tournaments (in fact my brother has paid for all 4 seasons). And there are other events like WCG (World Cyber Games) and other burgeoning E-sports competitions that are slowly making names for themselves. On the latest season of NASL, the commentators mentioned that ESPN--freakin' ESPN--was considering putting them on one of its channels, but the commentators speculated that the older generations are not yet ready to accept the growing community of competitive-gaming as it is. With a large number of the baby-boomers approaching an age where they are ready to retire, the newer generation is ready to take over--a generation that is more accepting of video games.
The long point I'm trying to make is that I think there WILL be some faithful video-game-to-movie adaptations, but just not yet. Things like comics and books can get made into good, successful movies; just look at how profitable Nolan's Batman trilogy, Peter Jackson's LOTR trilogy, and the Harry Potter series were. Comics and books are "accepted" so people take serious attempts to make good (and faithful) movie-adaptations, and I feel that video-games will eventually be too. Just not yet. Within our lifetime though, we may see them become popular enough to attract a serious director's eye.