It probably does violate standing diplomatic agreements with the PRC over how that sort of thing would be handled. There was a lot of pushback in Taiwan because they saw it (correctly) as pointless pot-stirring.

Anyway, I think most of the flights that aren't innocuous (and many of them are or they wouldn't need to have such bullshit articles) are drills in preparation for the possibility of the US using Taiwan as a military platform as it has been angling for in the past. They aren't just dick swinging or whatever, China doesn't want to take any risks in the event of a military conflict, though it would prefer such a conflict not take place.

This is the epistemological stumbling block of living in the west, is this cultural remnant of christianity that compels us to view all things first and foremost through the lens of good or evil, moral or immoral, fault and blame.

States are not perfect frictionless spheres floating in a vaccum and acting purely off some set of moral principles. They are enormous machines rooted into existence by countless interfaces, big and small, with the world as it exists. A state operates on material conditions, on probabilities, contingencies and eventualities. The number of trigger states in a computer is nothing compared to the volume of procedure and protocol involved in the running of a society. With this in mind, the more relevant question to ask with any geopolitical event is not "Who is morally responsible for this?" but "Is this outcome a logical one given our understanding of the factors at play?"

Taiwan could refuse her entry, tell her pilot to divert, but the ROC regime still let her in.

Hate to break it to you, but even the US state department recognizes that there's no such country as Taiwan. Please call it by its correct name, "Chinese Taipei," so people know what you're talking about.

or

Which way, western man?