Yeah, I'm sad about this too. I sort of knew the counter was there, but never paid any attention to it... until very recently. I started to use it as a self-motivating tool to always do even minimum amount of work one of the numerous after-hours projects I have.
So now that I started to use it, they cut it out. sigh
There is an analogous productivity method called "Don't Break the Chain" involving a prominently-placed real calendar, and big red crosses denoting daily successes. It triggers the same (rightly) proud sensation. Anecdotally I preferred it to GitHub streaks (as I rarely look at my profile).
Any habit tracker site/app will also do this for you - I automate mine with GitHub API data, and get a similar effect (the app notifies of streaks daily).
So now that I started to use it, they cut it out. sigh