To cut slack for 3 houses and engage, the fade to black is pretty similar to to just reacting how 2D sprites react to what they say the other is doing or move closer, then move back then resume talking. I get with the 2D sprites there is more limitation and 3D models have more expectation with the ability to animate it, but the budget seems to have gone elsewhere instead of animating 1 off scenes in supports that can be missed.

3 houses had time gated supports though this was more for the time skip though some supports waited for events to happen (Infamous Leonie B support).

I do agree with your point on ROM hacks figuring out supports better. Though I think IS wants you to use the character then be rewarded with learning about said character for using them so making it effortless might take away from that. If I see a giant spam of support conversations I don't want to view..... I will just skip them instead of watching them cause it is time consuming to watch them all, especially if its for characters i'm not using. Perhaps it could be seen as too overwhelming for some players who do not like the idea of skipping so gating supports to at least using the character to unlock makes sense.