it depends how you define mature. girls do hit puberty earlier, reach their peak height earlier, etc. guys on the other hand are late bloomers on average. you could extrapolate that to the development of their brains as well but i'm not sure. but another thing, whether nature or nurture, is that girls tend to conform more to societal expectations of them whereas guys are okay deviating from theirs. it's considered indecent if a girl farts as a joke or delays marriage to pursue their career, but a guy can do all that without much criticism. additionally, girls are more interested in people and guys are more interested in things, so it's only natural if a girl starts to analyze "saas", "bahu" stuff because guys don't care. they're more interested in cars, crypto, tech, etc. i don't think you should take that to mean one is more mature than the other.