Lego comes for all things, to pop culture as English is to other languages.
The concept for the set was submitted to Lego by Viv Grannell, a Sonic fan based in the UK, through the Lego Ideas program. Submissions need to receive 10,000 votes before Lego will consider making them an actual Lego set, so it's no small feat that Grannell was able to get the necessary support for the idea to become a reality. If you want to see more pictures of the concept, check out Grannell's page for the project on the Lego Ideas site.
Not the first Lego Sonic (e.g. Amazon) but clearly the best.