I don’t really think a one-size-fits-all approach works here. Largely because movies are collaborative efforts. Is it fair to all the other people who worked on American Beauty if we strip that movie from our collective consciousness just because of the actions of one person? I’m not sure that it is.
That said, my own personal interest in watching Kevin Spacey films has plummeted… but there are exceptions to that rule.
Namely, David Fincher’s film Seven. I still watch Seven, and all the shit that has come out about Spacey hasn’t diminished my enjoyment of that film.
Perhaps that is because Spacey plays a key role but not a lead role. It’s much more of a Brad Pitt/Morgan Freeman movie than it is a Kevin Spacey movie. And it helps that Spacey is playing the bad guy—you’re already supposed to hate his character, and the accusations against Spacey just help me to hate his character even more.