What's important is building simple things that people can use." Web 2.0 is a people-oriented technology movement. Ease of use, social features, collaboration, fast-loading applications, interactivity, quick development times and real-time updates are all major trends. They look more like desktop applications.

Web 2.0 still works. But it is not as effective as your are making Blogs on different Web 2.0 Sites. And these Blogs have zero domain authority. So these type of Backlinks are not so worthful.