In a nutshell: During the initial part of the crisis, landlords let people live for free in units when they couldn't pay their rent. Then the government decided to tax the landlord on occupied units, even if they weren't getting any rent. The landlords could not afford this, so they began throwing families out into the street wholesale.

Most people did not actually starve to death during the Potato Famine. Most died of disease due to eating raw food in desperation and already being weakened from malnourishment. The families that took it the hardest were those with less than X amount of land who also had many children because you can nearly live on potatoes alone, so such families exclusively grew potatoes and nothing else. They were wiped out by the potato blight and had nothing to eat. Families with fewer kids and/or larger plots of land had other crops too, not just potatoes. They were hurt, but muddled through.

Farms under a certain size essentially disappeared due to the Potato Famine.

Famine was widespread during that time. Most countries were hoarding food and trying to buy it. Ireland was on a short list of countries selling food to make a buck during the crisis. This is part of why Ireland was hit so very hard.

Magicking up money does not solve the problems of the lower classes. They need access to affordable housing that genuinely works for them. They need rights. They need access to paid work that fits their crappy lives.

The UBI provides none of that. It is a disaster waiting to happen.