From the release notes.
Note however there are still some missing features
and performance problemsin the new implementation. Particularly animation playback and moving of vertices in edit mode will be improved before the final 2.80 release, to bring it back to 2.7x level.
Further optimizations and features to be added later in the 2.8 series:
In short, the devs. are aware of the issues and have plans to work on them. It’s just that Sergey also has a bunch of depsgraph and modifier bugs to deal with too.