That daily misery is still likely multiple times better than what it would have been 100 years ago. You may consider it misery compared to your own standard of living, but it's entirely possible that 100 years from now someone may consider your current situation as "misery" as well.
If you asked these people you are referring to whether they would rather continue on as they are or be put out of their "misery", I suspect we both know what the answer would be.
Additionally, I don't think it's any more useful to prioritize comfort of all living people than it is to prioritize advancement of the species as a whole. Focusing on both to greater and lesser degrees is worthwhile in my eyes, and advancing the species to the point we can get off planet and colonize other locations also vitally important in my eyes, as making everyone more comfortable (which is not the same as happier) is pointless if we're extinct in 50 years when we could have prevented that.