One doesn't need to replace the other.:)
The big problem with matchmaking is that in the long run, it kills game. When people start to move on to a new thing, the population that stays because they're attached to the game gets fucked over by matchmaking.
The less people they are, the worse it works. That's when a server browser and the ability to run community server becomes crucial. It will keep a game alive for a decade after its last update.
It's not extraordinary but hey, small wins are still wins.