US wargaming had repeatedly found that escalation to nuclear exchanges is all but a given if serious attempts are made by either side to destroy naval and air base capability, and it's safe to assume their PLA counterparts reached similar conclusions.
As an example, in a Chinese move against Taiwan or Japan, anything that crossed into attack range would get destroyed, but there would be no counter-attacks against Chinese facilities and bases. Does that play out in reality? Let's hope we don't find out.