To illustrate why that is, think about a state like Ireland. So far, Ireland has gotten corporations to be HQ'ed there, or pay taxes there, because the tax rate is only 12.5%. The detriment for Ireland has been minimal, if any, from that corporate presence. It _could_ have gotten more but that's just theoretical.
If this goes into effect, then a corporation will no longer benefit as much from being Ireland-based: It will pay 12.5% corporate income tax annually, but will pay extra in other countries it's active in. Who's going to subsidize the extra 2.5%? Ireland? Technically possible, but it's unlikely for Irish politicians to subsidize the taxes a private corporation pays _elsewhere_. Showering a corporation with money to that extent requires corruption on a whole new level.