So every navies around SCS want a piece from China, and ROC forfeited their own right of SCS claim for military support. If Taiwan really do this, that will possibly be the last thing they could attempt before the proper warfare burn upward to the entire Eastern Asia. Which will be chaotic.
While a bit unlikely, it is still a propable scenario.
Lately, the new ruling pro-independence DPP party in Taiwan was accused by their opposition and the Fisher Union as 'sell-outs' for their weak-ish stance against the Philippines and Vietnamese, and for 'buckling' to US and Japanese pressure. The result was that the DPP caved in and still sent some patrol boats to Taiping Island, as well as joining China in ignoring the PCA ruling. But despite this, there is sign that President Tsai and the DPP actively works towards the goal of shedding the last bit of 'Chineseness' in Taiwan, by forfeiting their SCS claim that they inherited from their status being the Republic of China.
Japan and the US would generously reward them for that, but not all Taiwanese would be happy, since the economy heavily depends on fishery in the SCS, and the Taiwanese held island remains a symbol of defiance for their already heavily embattled sovereignity.
I would say that the ROC forfeiting their SCS claims would only happen along with the ROC renaming itself to Republic of Taiwan, hence officially declaring independence and inviting war with China.