Looking at the available jobs in Dublin for e.g. Google, I don't think that's wholly accurate. Ireland's tax story does attract US multinationals, but they're not just shell companies.
At least until a few years ago, large corporations had their support centers in Ireland (Dublin), but the focus may have shifted in time.
The specific engineering positions[¹] seem to have a significant rate of customer support/sales/market; it seems that Ireland isn't a technical research center. I haven't looked at how the mix of open positions is in SV/USA, though.
