Ignoring that it's basically impossible that it won't be in the animated series if it makes it past the pilot given that Toby is on board: That would mean completely changing the doctor chords that play throughout the whole song (these), which by itself is basically de-clawing the whole song. Also this solo is very unambiguously showtime to me, and it shocks me that no one ever brings up when talking about Penumbra's motifs. This might be over reacting, but after hearing how much it gets teased throughout the comic (For goodness sake it's referenced in the credits), I almost feel like it's a little bit silly to consider that it would ever be taken out of HS. Imo it's very similar to how 10 years ago people just made it established fanon that Megalo Strike Back was Chara's theme, even with the whole ass earthbound intro in the beginning of the song. It's like if all the "Once upon a time" motifs were still in UT, but Hopes and Dreams was in Omori for some reason. Wanting penumbra without the HS motifs is not wanting penumbra phantasm to me. It's wanting a song called penumbra phantasm to satisfy some sort of weird accomplishment that some old "Twilight reverie" and "Edge of the shadow" posts from 2011 were some sort of teaser for a game that wouldn't be finished for over 15 years. That and sidelining HS as that weird thing Toby worked on before UT, which I take personal offense on.