Fair points, and I agree. However, I believe that the double-irish loophole is more of a 'value add' for the big companies already here, to lessen their tax load in other countries via 'convenient' accounting. The EU ruling is more about this tax evasive nature/use of the loophole than the investment in Ireland and it's economy & jobs.

Edit: The EU ruling actually targets a specific use of this loophole by Apple, which alleges amounts to state aid, hence the anti-trust comments. (Gotta love the HN community for delving into the details)