In situations where definitive proof of any clear reason does not exist we are left with the facts presented to us and probabilities.
Again...this has nothing to do with politics. I am merely looking at things from the view of an outside observer.
There are many more valid reasons to limit Chinese influence and "data gathering" but they are largely (at this point) being ignored. This does not begin to dip into the actual "political" reasons both countries involved have going on.
There may be no definitive proof, but it's not nonsense. Trump has made clear on many occasions that whether or not a group supports him is always on his mind. He's made clear he would ban Twitter if he had some legal cover to make it seem legitimate.
No other reason. It ties in neatly with the revenge track record and the timing of events ties in also.
(Just the facts, I have no political view towards either side)