Great that IE is 12%, but this "competition" is BS in the sense that they needed the higher-tax countries to bail them out just a few years ago:
https://en.wikipedia.org/wiki/Post-2008_Irish_banking_crisis
It's a leak in the EU system, and it needs to be plugged.
Just imagine what a unified income tax rate in the EU would do. (Post-Brexit, although if I were a gambling man, I'd wager that the Brexit will never materialize; A Brexit would sort of be like throwing out your existing post-ww2 source code instead of refactoring. Recipe for disaster).
THEN countries would really need to compete on quality of life and infrastructure to attract (US) corporations to establish show. Amsterdam is happy to welcome all the post-Brexit (see comment above) banks and EU-related orgs, as is Frankfurt.