This isn’t “how to start a company in Taiwan”, or any of the other generic business threads I’ve seen so far.
This is strictly relating to advantages (and disadvantages) for foreign corps (American in this case) to establish a legal presence in Taiwan.
This could be financial, (tax advantages, import/export duty loop-holes etc), or administrative, (e.g. we have one contractor here already and looking at possibly more, but it may be easier to attract talent with “proper” employment, benefits etc).
From what l know, the main advantage of having a presence in Taiwan is being able to issues Fapiaos, i.e. official invoices, to Taiwanese customers. If you don’t have those (or lots of Taiwanese suppliers), then having a presence in Taiwan doesn’t make much sense.
Other reasons could be visa-related (then a branch office might not be enough) or if you want to hire local employees.
The main advantage would be that you can have a proper team on the ground to deal with Taiwanese customers if you consider the Taiwanese market attractive enough.