You are not a "boomer" if you aren't in your twenties. You are not irrelevant if you aren't in your twenties. You don't go straight from being a kid to being "old". Stages of life are fluid and vary for each person, and should be savored to the fullest of your means to do so.
Stop letting internet memes about age, height, and general state of being have an actual impact on your mental health. They mean nothing, and don't benefit you in any material way.
edit 1 part 1: this is the worst comment section I've even seen in any Hexbear thread in all my years, except for @Dirt_Owl@hexbear.net who is as always the best of us
edit 1 part 2: generationalism is also made up, don't let people put you into boxes and further don't put yourself into a box that someone else made up for you
Thinking about it in terms of being "young" or "old" has always been a pretty toxic concept to me. Everyone matures physically and mentally at different rates in countless different directions throughout their lives. Just think of yourself as an "adult" and don't slap artificial limitations on yourself, because doing so is kind of a tragedy.
And lamenting growing older sucks even more, when you consider that a lot of people don't get the privilege.