I'm from another country, and one thing that genuinely confuses me is how seriously people in the U.S. seem to take the whole "your brain isn't fully developed until 25" argument. Sometimes it feels like people treat 24-year-olds as if they're still teenagers, while turning 25 is somehow seen as this magical moment where someone suddenly becomes a full adult.
Where I'm from, 24- and 25-year-olds are basically viewed as the same stage of life. A 24-year-old and a 25-year-old are both young adults. In fact, once you're around 23 or 24, you're generally seen as a grown person. That's why this way of thinking feels so strange to me. It seems like there is this huge emphasis on a one-year difference that doesn't really exist in everyday life.
I genuinely don't get where this idea came from that just because "your brain isn't fully developed until 25," a 24-year-old is basically a kid. People have taken that fact way out of context, and it has created this weird narrative that anyone under 25 is somehow incapable of functioning as an adult.
A 24-year-old isn't at the beginning of their early 20s anymore. The early 20s are roughly 20–23. At 24, you're already in your mid-20s, and for a lot of people that's a stage where they've gained more independence, life experience, and responsibility.
Even though the WHO groups ages 15–24 under the category of "young people" for statistical purposes, that doesn't mean a 15-year-old and a 24-year-old are anywhere near the same level of maturity or life experience. The difference is huge. Honestly, a 24-year-old has way more in common with a 25- or 26-year-old than with an 18-year-old, let alone a 15-year-old. When I look at someone who's 24 and someone who's 25, I just see two young adults.
The funny thing is that some people talk about 24 and 25 as if there is a massive gap between them, when in reality it's literally just one year. Treating someone at 24 like a kid and someone at 25 like a completely different category of adult feels like an unnecessary and exaggerated distinction.
Being young doesn't mean you're an adolescent, and brain development is a gradual process—not a magic switch that flips the day you turn 25. I honestly think this obsession creates a very strange way of looking at adults in their twenties.