A million died, at least a million emigrated. The population never recovered.
The potato blight did affect other countries, but those other countries had their own government, situated in their own country, and those governments were willing to help those affected. Ireland had none of that.
I have always tried to be balanced about the Famine, in which many of my ancestors died. I have always pointed out that the British government operated a policy of laissez-faire, assuming the market would correct itself; and did not realise that the political and social exigencies present in Ireland meant that there was no such “market” in Ireland – in short, that the British parliament was mostly just ignorant and ill-informed, with only a few deliberately genocidal elements like Charles Trevelyan.