The article doesn't really distinguish between offering help, and pushing your help. I work in a large team, and I often work on some obscure feature, and it's not always clear who has experience with it. If someone notifies me "hey, I have experience with that part of the codebase, I'm here if you need help", that's what I call offering help, and that is very useful. It's still up to me to decide if I need help or not.