I wondered about this as well, and my theory/overgeneralization is that this may speak towards the general mindset of the average Integra 6MT buyer. We want something that leans towards sporty and fun, but we're also adults here -- we like our nice interiors, and maybe we're not trying to get the loudest car on the block, figuratively or literally (we have the Elantra N for that!). The red interior seems like a have-your-cake-and-eat-it-too option, in my eyes; it's splashy enough to make the new owner smile, but the exterior is still muted enough that you probably won't raise any eyebrows on a spirited drive. I'm sure some folks hate it, but I personally think it's kinda neat. I went with the Liquid Carbon Metallic on my reservation as it was kinda-sorta subtle, but the louder interior kinda offsets some of that. My lizard brain can't help but go "huh huh, racecar," even though my rational brain knows that's not really the case.
I will say that the white is growing on me a bit. I'd also be cool with black over red if it were available; the blue over red seems like a bit much, but hey -- the dang thing is proudly made in Ohio! If you can get that combo and want to lean into the 'Mericuh vibes, I can't hate.
The black interior is probably fine, and it's fair to say that it's perhaps a better choice than Orchid for a lot of us (kids/dogs/etc.), but it's visually less exciting, simply because it's very monochromatic. The Orchid interior might get dirty very easily, but it does have some panache. Contrasting seats and panels really make an impact, practicality be damned.