We have war every generation because leaders have forgotten how horrible war can be. It SHOULD be avoided. Putin, Trump, and Xi have never known that (unlike JFK, Bush Sr, or Stalin), and are too anxious
to approach the brink. Xi has been consolidating power, even killing people who thought the invasion of Taiwan should be delayed.
Now is objectively the best time for Xi to attack (that doesn't mean it's a good time, it means the US is at its likely weakest point and a similar opportunity will not present itself). It's been widely reported that US air defense missiles are running low, and production is ramping up. Every year that passes, Japan, the Philippines, Taiwan and Korea become stronger and anti-drone defense will remove China's temporary drone advantage. America is distracted in Iran and Ukraine, but that window of opportunity
will end, and American military power will focus on the far east. Now is the window, and the time to strike is when the US is maximally entangled in Iran (ie, when it becomes apparent that the US can't become
more entangled).
All of that is non-controversial. The question is whether Xi actually chooses to move militarily, then we are in WW3. A sample scenario could be like this:
1) At their meeting next week, Xi tells Trump to stay away from Taiwan (and the south China sea) or they will let nukes fly. (You don't attack us, we don't attack you).
2) The PLA encircles Taiwan, and moves to take control of the Philippines west of the 116th meridian east.
3) The world can't believe what happened. After a period of deliberation, the US sinks their navy.
4) The blockade is broken, but rather than confront the US directly, they send a nuke to Japan in the desolate area northwest of Kyoto.
In any case, the time period for testing this hypothesis runs out a little while after the Iran war ends (ideally, at the point when it becomes obvious that the US will not become more deeply entangled, but China may miss the exact timing and still choose to move, so the hypothesis extends some months after that point, with decreasing probability as each day passes).