You're completely missing the point. Most people are not logged in to any of those services all the time. That fact alone prevents it from being a primary source of communication. All the other factors I mentioned are other reasons that desktop IM clients (even if used on a phone) cannot be compared to BBM. They're not the same. They never will be the same. They need to stop being compared by people who have never used BBM.
I used BBM for years and PingChat is the closest thing I have found. It can only be used on a phone and you cannot log off. The only way someone is not on is if they delete the app.