Ionic makes development easy as it integrates with your popular framework or library. Ionic has official integration with Angular and React while Vue is currently in beta mode. In the previous versions of Ionic, it was tightly coupled to Angular (based on the fact that the framework was built on top of Angular) but now it can work with any other framework of choice (React, Preact, Vue) or with no framework at all.
You can build great web apps, mobile apps(both Android and iOS) and desktop applications all from one code base. No need going through the stress of learning different languages for different platform. Ionic take all that stress away from you so you could focus on the most important task (Building Your App).
Ionic Framework is a free and open source project, released under the permissible MIT license. This means it can be used in personal or commercial projects for free. There are millions of Ionic developers in over 200 countries worldwide. You could join the community by following the official Twitter Page to stay updated about the latest information, or joining the Slack to meet and chat with other developers. The official Github repo where you could report bugs and/or request new features or you could also join the Ionic Forum for asking questions and sharing Ideas.
Ionic overall is a great framework that's easy to learn and get started with so I'd advise you jump right in and experience the awesomeness of the framework