robert, The Neos Team has been working on a new content repository for the last 8 years. What took us long? The new CR is event-sourced, with sophisticated projections and a thoroughly designed PHP API, something which has not been done before, not even outside the PHP ecosystem.
Here are the slides for the talk @sebastian and me gave today at the International PHP Conference in Munich. Ping us, if you have any questions or feedback!
https://www.slideshare.net/robertlemke/neos-content-repository-git-for-content