It would depend on the survivability of SHORAD, in addition, smaller tactical drones will not survive in a denial environment, regardless of the level and intensity at which they are inserted in the theater of operations.
This kind of comparison is not even remotely valid in any respect, especially since the LDPR was more like an armed militia than a conventional army, despite the AFU having suffered against them in 2014-2015. Even if you compare Ukraine and Russia by making an analogy between China and Taiwan, it would not be considered valid either, because Taiwan has more than 250 4th generation fighters, which means that the ROCAF is much more powerful than the Ukrainian Air Force, which had 100 4th generation fighters, Soviet fighters at that, although the PLAAF is more powerful than the VKS, the analogy is inappropriate and if we are to base ourselves on making such comparisons, the definitive statement is that Taiwan has a much better chance of gaining air superiority than Ukraine could ever achieve. Such analogies are useless...
No one denies that the difference in capabilities is very large, but this in no way means that the battle is lost or won depending on which side we are referring to, it would be like the saying that planning/plan does not survive the first contact with the enemy, this is still an unknown to be revealed when hostilities begin.
What decoys? Does China have MALD?
Taiwan’s GBAD is based on seven Patriot batteries and seven Skybow II batteries that are supposedly similar to the PAC-2-equipped Patriots. In addition, there are 14 Skybow IIIs. All this on an island much smaller than the Kyiv Oblast makes SEAD missions very, very difficult even for well-trained air forces, and China has never had to conduct a real SEAD mission. The Russian VKS is an absolute farce in this field, but at least they have some experience flying in hostile skies over Syria. The same cannot be said for the PLAAF.
As I have already said, air denial can render an enemy air force, which has nominal superiority over its own air force, incapable of effecting its presence on the battlefield (through fire delivery) because ground assets like GBADs have made the environment too dangerous. Taiwan could certainly contest PLAAF tactical air superiority over Taiwan's skies, because that is what would inflict a force multiplier for amphibious forces landing on the beaches, but as I reiterated, that would depend on the circumstance of how China would execute the AR.
Forget the US.
At no point did I talk about how to approach an assembly area to apply armored mass principles to execute armored counterattacks against Chinese amphibious units on the beach, I talked about that in a post that has nothing to do with your comment, which was in another context, your context is about Taiwan's air strategy and its implications on the operational approach to land operations on the coast. As I said, there are different ways for the ROCA to pursue the PLA's strategy of attrition of its units pressed against the coast, the ROCA could do this even if it had lost the ability to deny Taiwan airspace to the PLA.