I strongly disagree. Personally, one of the main things that I look for in a videogame is a good soundtrack. If the soundtrack fails to to draw me in, then it's very unlikely that I'll complete the game.
That's not always true, of course. I'm a big fan of Bioshock, for instance, even though there's very little music in it. But whether it's Bioshock, or Fallout 3, these games are exceptions to the rule, not the other way around. As a good counter-example, what would Mass Effect be, in particular the first one, without that fantastic Blade Runner-esque soundtrack that it has? Sure, it would be a nice enough futuristic RPG, with an ambitious story, but the soundtrack really helps put all that in perspective. Hell, even Half-Life, a series known for its minimal use of music, has a couple of kick-ass songs playing during intense moments, and you wanna guess what moments people loved the most in those games?
So, no, I don't think that music will become irrelevant in games. From the contrary, I think that music will be crucial in the future of videogames, as it's one of the most immersive qualities a game can have.