Given how much of Foxconn's operations are based in mainland China
Would he really be who a Taiwanese resident would want to be in charge? Would he act in the best interests of Taiwan or in the best interests of Foxconn if a conflict with China was looming?
His potential conflicts of interest make Trump's foreign conflicts of interest look like chickenfeed by comparison. The idea of electing someone with business experience is a good thing, but probably someone with experience in a small/local/regional business. Not international business, finance or real estate. Their interests and that of the country may have much less overlap than you would like.