Generational rivalries usually come out of some form of resentment. Typically, this resentment is that "kids these days have it so easy! Everything was difficult when I was their age, and now they don't have to withstand any difficulties!" Every generation has it hard in a different way, and there's no point in endlessly playing the "who has it worse" game. Even though we know this is a fruitless and meaningless debate, we can't stop participating in it. It's just too much fun to rag on the young people. I do it, too, turning my nose up at kids who never played outside and had an iPhone from when they were six years old. It's irresistible!
Although this cycle of discourse often can't be helped, you can choose whether to approach it in a lighthearted or deathly serious way. One Gen Xer recently waged war on millennials on Twitter dot com, and his serious approach has not been received as gravely as he intended.