just a correction here, Taiwan does not have modern subs, or even modern f-16s they have the a/b version which is frankly comparable to the mig-29's that Iraq had, however Taiwan's training is better. with respect to frigates their level of tech is not above PRC and the PRC can bring a hell of alot more to the area, but its absolutely true that Taiwan would be able to hit back at the mainland at least initially but the damage would be fairly limited, after about 1000 SRBMs are launch we can discount, for all intents and purposes, the ROC airforce.
but the biggest concern above all else if war started is the actions of the US, here its a race, how fast can the PRC overrun most of Taiwan before the US can make a decision and send enough forces to the area to make a difference, i think we all know the results if the US dont intervene
of course there uis also the consequence in the after math of this war if it were to happen but thats beyond the scope of what we are looking at here.