Fair, I meant to Nancy's plane specifically. I also don't think China will use this to rush an invasion of Taiwan, at most perhaps take some of the islands (i.e Kinmen) like we saw with Crimea in 2014.
Taking Kinmen would be beyond stupid. It has no strategic value (for China anyway) and will simply become a place for Taiwanese intelligence to fan civil unrests. Also that's a one-time thing. What happens when the next Western politician come? Take another island?
A PLAAF flyover is better. It asserts Chinese sovereignty and it's infinitely repeatable.