I approach it not from a perspective of "taste" per se, but from a perspective of purity and truth. All of these techniques (AI upscaling, colorizing, interpolation, etc) are adding information that was never there, which means you're no longer watching the genuine media.

By all means take the original film and rescan it in the highest possible resolution, to capture all the information that was in the film, but to add information that wasn't there to begin with is going too far.

It's like all the modern TVs that have the horrendous "motion smoothing" feature, which is enabled by default, and makes movies look like soap operas. When the TV performs frame interpolation, it's adding information that was never there, and wasn't intended by the director.