Maybe you're arguing that standards can be inferred by published events. Sort of. I think that was always the goal for NIPs. But that's like saying documentation isn't necessary, just go read the source code.
Static documentation isn't necessary, it's true, but it's useful marketing material or a basis for discussion. Nostr has a built-in incentive for people to use other people's events, so that they can capture part of the same audience. An open protocol is a novel idea whose time has come. We're just embracing it.