The research does not necessarily indicate that boys are slower to mature. It is just as reasonable to conclude from the experiences mentioned that the school system favours girls.
If boys are more likely to miss important test instructions, this may not mean that their brain development is slower. It could just as easily mean that written instructions appeal to female skillsets and that audio instructions or visual instructions would result in fewer boys making examination mistakes.
Similarly, the lecture model at university, where students sit still, pay attention and don’t speak, might not be the best way for male students to receive this information. As a result, female students take better notes.
If the school system did not favour students with strong reading proficiency, organisational abilities, and self-regulation skills, then boys and girls might be on a more equal footing. Maybe boys are slower to mature. But it is the responsibility of the school system to take this into consideration and take steps to stop boys falling behind academically.