That was actually understood a decade ago as well and was part of the conversation that led to OpenID and OAuth. It was suggested close to a decade ago that the

That was actually understood a decade ago as well and was part of the conversation that led to OpenID and OAuth. It was suggested close to a decade ago that they both merge efforts and they have both struggled to find their place. Development on this scale just lags a bit behind, specially when the community around it is so fragmented and opinionated.