Thank you for responding irshadshalu, I sincerely appreciate you taking the time. I agree that HN works in unpredictable ways. I don't know if you were just more lucky than I was, or if people like your app better because the UI looks better. If that's the case, it's interesting to know.
This HN account is new-ish, but the original MusicToy blog post from 2012 is still around [1].
As far as Git goes, I would appreciate it if you had an acknowledgement somewhere that linked to the MusicToy repo[2], or just mentioned in passing in terms of inspirations/predecessors. You obviously have no obligation to do this, but it won't take away from the success of your app if you choose to do so.
I wish you the best of luck in your future endeavors, and may your success encourage you to build more great projects.
[1] https://pointersgonewild.com/2012/04/23/musictoy-music-made-...