My experience, coming from the 1DXII to the R, is that shooting kids moving erratically around with large apertures (f1.2-f2), the R gives me way more keepers/in focus images, and that experience was with the first EOS R firmware. The R has improved considerably with the newest firmware.
For some types of action photography, like birds in flight, a DSLR may hold an edge, and the optical viewfinder will probably be better as well. For most people and shooting scenarios though, the AF in the R outperforms every DSLR ever made.
I use the R and the 5DIV every week, and when using the 5DIV I am constantly bothered by slightly out of focus images.The constraints that comes from having to using the focus points is also bothering me a bit.