It is a reaction. China does not want to escalate tension unnecessarily. China is still wanting to work with the US. 合则两利 is what China says for the time being.If the objective of these exercise is to deter those visits, it is a failure. Like Russia warning of nuclear weapons in Baltic if Sweden and Finland join Nato
The US obviously is taking advantage of and abusing China's self-restraint.
But China's patience might have been wearing thin.