Many millennials hate boomers because they're 'selfish' or whatever.
The basic problem is there's a huge disconnection between the boomer generation and us, even Gen Ys like myself. They grew up in a world (in Murica, at least) where a comfy life with decent job and loving family was effectively automatic, as long as you didn't fuck up badly. Society is obviously extremely different now, and thus when communicating with boomers who cannot relate to this, they can be frustrating, to say the least.