Why do we need cars when we have horse carriages?
Maybe we just don't need it, but it's nice to have a different approach / a choice.
But Atom is free, open source, and actively being developed.
You don't know if something will eventually become better unless you try hard.
Though, the enthusiasm there is nice and there is no reason to bemoan its existence. Just don't be surprised when the things it can do have already be done in more venerable environments in the past. :)