There’s really good documentation out there and there’s bad/nonexistent documentation. So stackoverflow is going to be a more consistent experience.
Also I think it is a bit of a skill to be able to read documentation well, especially for Jr. Devs that might not have fully grasped OOP.
But guys, if we use agile then we don’t need requirements! We just make something and then the customers tell us if we are on the right track, we just get to iTeRaTe