Earlier quoted context omitted.
What’s interesting is that it’s common for governments to give tax incentives to companies that will result in driving more economic value for their region. Eg Ireland might give a tax incentive if a large Fortune 500 company hires X people in Ireland. Question: does this ruling prohibit that common practice?
Kind of. It's already prohibited, depending on what you mean. It would be legal to say all companies can have a tax break if they hire X people in Ireland. It's not legal to give the tax break to one company and deny it to another.
That seems like a bit of a perverse incentive for countries to offer deals they may know will get overturned later because they'll get the money eventually.