Taiwan needn't consider that option yet but in the not too distant future military power in many more contexts do not belong to the biggest and most powerful always prevailing. Alternatives to nuclear weapons that do not include biological agents or chemical substances would be developed. The Israelis would probably get there first and Taiwan would be motivated to go down that road as well.
No wonder the Chinese are anxious to get Taiwan back. Strategic patience is extremely risky to achieving the return of the island to the mainland.