arda I don't think verification is necessary, as the official Flarum organization is linked multiple times from the Flarum website.
The only thing it could maybe be confused with is FlarumOne, but between FlarumOne and Flarum, I think most people will realize which is the official.
However, I am not saying verification wouldn't help at all. It just wouldn't help as much as one may think.
The official repositories are the first result when one looks up Flarum on Github or any search engine.
But, as it's such a simple process, it wouldn't harm anyone. Just yesterday I verified both ReDevelopers and ReFlar on GitHub.