Can you elaborate why there should be an incentive to move to regions?
All the infrastructure is in place to suit the current arrangement.
As opposed to piling ever new company within 25km of Dublin city center with the corresponding pressure it puts on Housing costs, water supply, traffic gridlock etc etc. Not a rural/urban divide but clearly the infrastructure in place can barely support the current set up never mind adding to it. Not saying every new company should be forced out of Dublin but clearly there needs to be a more long term balance adopted or else in 50 years most of the population will live in Dublin (prob a slight exaggeration but you get the idea).
From personal experience the state agencies do their very best to encourage companies to locate outside of Dublin but it ultimately comes down to the companies themselves. They want to be where Google and Facebook are, to share in that pool of talent, to be in that vibrant atmosphere. They insist on being within an hour of an airport that has flights to the US. If it's Dublin or somewhere else in Europe the state agencies have to go with Dublin.
As you correctly point out Dublin can no longer support this. The problem is that the energy spent on encouraging companies to locate outside of Dublin is too diffuse - they really need to concentrate on , say, Cork and Galway. Both are nearly there in terms of IT and Pharma. The air links are feasible - even Dublin based companies are flying to the US via London, Schipol and Frankfurt so as long as you have links companies can see the possibilities. Unfortunately both these cities are as gridlocked as Dublin with accommodation costs well above those in comparable European cities.
The thing is native Irish people could set up companies in these towns - but they don't - they follow the same criteria as the multinationals.