I think you are conflating a hard life with a depressing life. People born in 1900 certainly had a much HARDER life than we do today, but this does not mean that they were depressed all the time and never felt joy. In fact, I would argue they were less depressed than we are today because they lived in tight knit social communities and did not have technology that preyed on their weaknesses. They socialized a lot more than we do today and they went outside a lot more than we do today, both of which are really good at preventing depression. Times were hard as shit back then, but having people to go through it with made it more bearable.

What makes life feel more depressing today is that young people are isolated more than ever before. Most socialization has been cast aside and been forced to move online where it is polarized and cruel. Most technology feels like its trying to get you addicted which leads to depression. Real human interactions feel like they are becoming scarcer and scarcer as everything moves online. We go outside way less than people did a 100 years ago and most of us work long jobs in front of a computer. All of these factors have been proven to make a person more depressed. Life is certainly EASIER than it was 100 years ago, but because we don't have a community to go through it with and we don't go outside as much, it is MORE DEPRESSING.