It's nothing conceptually different from the US deciding to tax its citizens on their worldwide income even when they are living abroad. It's "completely independent of where they're actually doing business or living"
The Double Irish involves a company in non-Ireland country A doing business with a customer in non-Ireland country B, and routing that transaction through Ireland. I have no issue with either A or B deciding that they ought to tax this transaction, because both countries are relevant.
If large corporations can decide to pick their country of incorporation freely and according to what most benefits them, but people can't (in general) pick their country of citizenship, then something has gone wrong.
After all, there ARE countries where more or less anyone can relatively easily become a citizen, it's just that most people don't want to actually live in those countries.
Some countries give people easy visas on arrival. Others make you jump through several hoops. Why? Perhaps this works out best for both groups of countries. The first group benefits from the tourism dollars, the second group perhaps sees benefits from not having the country flooded by tourists who might or might not leave easily.
I'm not sure where this fits into your argument anyway, but I could not identify what country you might mean? https://en.wikipedia.org/wiki/Naturalization#Summary_by_coun...
A (low) bar to residency which leads to being eligible to apply for citizenship after a several years' commitment (also being highly dependent on any political change during those years) is not what I would call an "easy" process.