Well, I see where you’re coming from, of course, and you’re welcome to send them an email, I think, if you believe the game is worth a look.
If you’ll excuse the TL;DR and not take this the wrong way, I’ll share a couple of personal opinions that are mine and mine alone:
I’m afraid a significant amount of people may experience adverse reactions in seeing the words “retro” and “platformer” being paired in 2019 - bonus points for being “hard as nails” (as it seems Horace suffers from difficulty spikes).
Basically platformers are a dead horse flogged, off the top of my mind, I wouldn’t know how many pure platformers RPS cover these days.
I can name Cuphead? The other side-scrolling games I can remember are usually metroidvanias or rogue-lites, which remix and reuse platforming in a different format.
While I mean no disrespect, this game might actually be 7 years too late, sad as that may be.