In part, this is wise of Taiwan. Provoking a faster Chinese military buildup--even if Taiwan can balance it somewhat--will also adversely affect America's ability to penetrate more effective Chinese defenses in the western Pacific to reach Taiwan to help fend off an invasion.
So if Taiwan can't in the long run build a sufficient military with their much smaller economy and Taiwan also wishes to maintain their de facto independence, another method of protecting themselves must be found.
Nuclear weapons are one answer, of course. Taiwan could build them. But that is risky if China decides that a preemptive nuclear strike is the only way to disarm Taiwan of those weapons.
Another way is to affect China's desire for Taiwan. If China stops wanting to take Taiwan, then the balance doesn't matter nearly as much. As unlikely as this may seem, when you rule out any other option of defending your island democracy, what is left is the only option. Yes, provoking regime change in Peking could be the only way out of the losing race Taiwan is in.
Taiwan may already be dabbling in this objective:
A Chinese student leader from the 1989 Tiananmen Square protests said Monday he had received money from a past Taiwan government through a fund that backed democracy activism on the mainland.
Despite China's growing power, China remains vulnerable to unrest.
Yet despite the hope that this approach holds of breaking out of the losing military balance, there is great danger, too. A Chinese regime under threat internally--especially if they blame Taiwan for that unrest--might decide that a war for Taiwan is just the thing they need to rally an angry population against an outside threat. Of course, China could easily blame Taiwan for unrest whether or not Taiwan is involved, so that fear should not be the basis for refraining from promoting democracy on the mainland.
At some point, the Taiwanese have to decide whether that risk is worse than the risk that China will gain the power to invade Taiwan at a time of their own choosing in the more distant future.