The Y-chromosome is a "genetic wasteland" in that almost every gene that could hop off it to go somewhere else before it got stuck has done so, because in an XY gender determination system the Y chromosome is less likely to be inherited, suffers in recombination events, and is more difficult to error check, so there is selection pressure to a gene to migrate elsewhere. (In the ZW system it's the opposite, where the W causes female gender development, ZZ is male, and WW is lethal) What that means in practical terms is that while the Y chromosome is extremely reduced in length, what is there is stuff that's absolutely vital to determining gender. So ion that sense it's actually more information rich than other chromosomes, which have lots of chaff and parasitic genes and repeats. With one notable exception in humans: Our Y chromosome has some big palindromic chunks so it can recombine with itself and prevent lots of errors, which has stabilized its size. So we're probably not gonna meet that weird fate some XY species have where they end up all female.