Why are millennials becoming so insufferable?

I swear I don't know what generation pissed me off the most between the boomers and the millenials. I used to admire them when I was younger because my older siblings are millenials now I despise this generation. They spend their time spitting on younger generation by saying the most boomers shit ever like " Back in my day" , " kids these days ". Their humor is so cringe. If I was a 2010's kid I wouldn't have any respect for them and would shows them off world's strictest parents episodes on repeat. I hope I won't become bitter like that when I turn 30. I'm tired of this narrative. Plato was saying shit like that back I'm Ancient Greek.