Like many things I've seen from Apple it will take a release cycle or two (of 1-2 years per cycle) to bring in this arguably basic functionality - as is tradition we'll groan about other issues being held back in favour of fancy new features.
I have no doubt they intend to fully compete with the email services from Google and Microsoft. Following on from last year we should see VPs taking us through the updates to iCloud+ alongside device launches as it expands into a fundamental service offering.