Yes, technically ionic is a for producing "hybrid" apps.. but it takes what you've created as an HTML5/JS/CSS app and wraps it into a native webview component, so that it behaves as a native app. And since it uses Apache Cordova to do that, you can access most/all of the native device functionality from javascript with cordova's api and various libraries/plugins.
So.. is it 'native' in the same sense that building an Android app in java, and an ios app in objective c would be? No, definitely not. The huge advantage it gives you though is one codebase that requires very few and sometimes no changes to work 100% cross platform. ionic simply provides some css and angular directives to make a web app (packaged into a "native" deliverable) behave like native apps, with minimal effort to build for multiple platforms.
If you also include CrossWalk you can avoid a lot of pain you might otherwise run into on android since it will use the chromium browser for the webview instead of the often janky half-assed broken android browser.
May be its good for prototyping but for real development, far from ideal.
Native apps will almost certainly always outperform a webview 'hybrid' app.. but if you want to build something cross platform you need a completely different codebase for each platform, and then you're looking at Java (android), Objective-C or Swift (iOS), and C# (Windows)
Personally, for most things I think a slight performance sacrifice is probably worth it to dramatically reduce complexity of building an app for multiple platforms... and being able to do so essentially just with javascript is pretty incredible.
So, really, what is ideal? Having to completely rewrite code to roll out another platform, and then maintain multiple code bases in multiple languages, or using one and maybe having to make a few very small tweaks for platform differences? I guess that largely depends on your time/budget and what you have available in terms of development team. Also, largely -- what it is you're building.
To just catigorically say "oh, that's not ideal for "real" development" is short-sighted and/or disingenuous.