Well, he does kind of have a point, clans do nothing for anyone as a player.
The only benefits are that you can always count on having teammates you know in tournaments. And that you will get invited into more tournaments. I don't think clans are problem, but I don't think they are absolutely necessary.
I have been in two clans, and left both of them, one collapsed after one player left and it took like a month to sort it out, and the other was completely disorganised and had no structure, clans aren't needed, it was a natural progression for the game, but it's just not necessary.