I understand the desire to make sure people aren't suffering, but can't we think about the suffering of future generations as well?

Paying for people to do nothing incentives doing nothing; fewer people will participate the more comfortable laying around gets compared to actual work. Worse, removing the natural selective pressures against low-IQ / high time-preference people means they will reproduce and leave the next generation with even more unproductive people for every productive person remaining to have to support. With IQ now negatively correlated with fertility, that's a recipe for genetic disaster and societal collapse.

Buying the happiness of our generation's underclass at the expense of who knows how many of their descendants when the system finally collapses under it's own weight is the opposite of compassion; it's just pushing the suffering far enough into the future that you hope you can't see it anymore. If we really cared about making people comfortable, why shouldn't we look for a solution where we promote the traits which lead people to build their own happiness in the long run?