alt Hacker NewsI firmly disagree with this advice as well; it strikes me as the sort of advice one comes up with when sitting around one's room wondering why one doesn't have any friends. The worst part about it is that it will get you doing all these activities that take up your time but don't really solve the friend problem.
Making friends isn't trivial, but it isn't a complex thing - just ask people you sort of vaguely know to hang out sometimes. Asking people to spend time together is about 10,000,000% more effective than any other strategy.
Do you firmly disagree with all of it, or just the clothes and gym part?
I don't have any objection to suggestions like "help people" or "be [a] good friend" or even "cook" and I think they're a core part of making friends. Today I cooked dinner for two friends and just got back from driving one of them home. They've been similarly kind to me in the past. Friendships are built on foundations like this.
It's absolutely correct that you need to invite people to do stuff before you worry about whether you're helpful enough, but you also need to go from being two or more people who kinda sorta know each other to actual friends.