Thanks! Music and programming were two inspirations for this game, so it's cool that the vibe carried through. Given that the gameplay itself only needed one button, I didn't want to require the use of more buttons purely for menuing. so I just did what felt like the most natural thing for the interface there.
I wasn't specifically intending a BIOS vibe with the graphics, but I'm happy to see you liked it! The artstyle was mostly just chosen to be readable and easy to implement. The relatively retro-looking font was just the monospace font (so that it would be easy to reason about what text would and wouldn't fit on a single line) with the most readable brackets that I had easy access to.