The Ireland of today is hugely better off than it was in the 80s and early 90s, and a good deal of that progress has been smart "marketing", as you call it, bringing in investment. Without this, the economy of Ireland would be closer to Greece or Portugal today.
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)
If those corporations leave then Ireland loses a lot of tax revenue.
Instead Ireland should tax property speculators.
The disagreement is between the European Commission and the Irish government. The deciding authority here will be the European Court of Justice, after appeal from the decision of the General Court - which favored Ireland.
Apple et al have 'made' billions of euros for the citizens of dublin in property value increases alone.