I mean, you're not wrong, but note that in 2023, Millennials and "25-to-39-year-olds" are one and the same. That is, I agree that this is not the best comparison, but the age range isn't arbitrary.
That's true, but it captures folks across such a wide range of stages of life as to be useless. Breaking it down into two to four buckets would make the point more convincing.