There's been dozens upon dozens of dope games released in the last couple of months alone, let alone the full year. Ya'll folks really need every last one of them to be 40+ hours long? Ya'll lack other things to do and have eons of free time or just barely play games throughout the year>?
Outside of RPGS or really heavy narrative-focused, action-adventure style games, most games in general weren't ever meant to be too long nor need to be. And as others have said, Metroid games have never been super lengthy either. Every meal doesn't need to be Thanksgiving's Day.
Yeah, if I was a kid or if I was hurting for money, I'd be mad about the length, but as a grown man I don't mind.
People kind of forget this came out of nowhere, they originally announced a Metroid Prime game, this was something to hold people over.