Mean while in a CodeIgniter far far away... I don't see why having some kind of auth tool built in to CI would cause anyone to walk away from CI. They have a choice not to use an auth system if it doesn't fit their needs, but to walk away from CI because of it? Unlikely!
When you look around the web at comparisons between frameworks, while CI is very respected, a common line is, "... but for some reason, the one thing it lacks is any kind of authentication system."
Sure it's probably not possible to provide a universal auth that can be dropped into any development and please everyone, but something that's simple to implement for basic auth needs would be useful. If you're building an advanced app then you will probably want an auth system that is beyond the scope of a bundled auth and you would take another route.
Perhaps we should stop and think who is actually using CI and what are they using it for. I imagine power users and large commercial devs are in a minority, and the vast majority are smaller devs building blogs and simple CMS systems and the like. At any one time I should imagine that a lot of new CI users are those who are looking for a framework and are trying CI out for size on a small project. In most of these cases they probably need a fairly simple auth that they can drop in to secure their back end or front and back with. It seems Ion Auth fits most people's bill. For the new users trying out CI to see if it's the framework for them, they are probably put off by the lack of auth, and probably strikes CI down on their leader board of possibilities before they have given it a fair try.
Personally speaking, when using CI I generally make my own auth systems. If I just require a secure backend I hash something together within CI and if I need user management on a front end I make something that fits the requirements. However, CI provides next to nothing to help me do that, and there are very few (if any) applications I build that don't need some kind of auth, and I imagine that goes for the majority of users.
To me, some kind of baked in, configurable auth, or at least the components to custom build one, seem like a natural pre-requisite of a good framework, and I find it hard to believe that anyone would walk away from CI if it had a feature that can be found in other frameworks.
