The Canon RF 28-70mm F2 is certainly an impressive lens, but it's $3000, weighs over 3lbs, and is huge. Your needs must be far more sophisticated than mine, but I'm probably never going to buy something like that and it certainly isn't going to be something that would entice me to switch brands or move up to a new platform.
On the other hand, the more pedestrian Z-mount 24-70mm f/4 (and not the camera) just might lure me into the mirrorless fold ahead of schedule. There aren't any F mount 24-70's out there that really excite me. If the image quality of the new 24-70mm Z-mount is anything like what Nikon claims it is, it'll be plenty impressive as a lightweight, compact, and (relatively) cheap 24-70mm that's sharp. From my limited opportunities to try one out, I was impressed with the weight, feel, and build.
So, I'm not disappointed at the lens choices at launch time. Anything I'm shooting at f/2, I'll probably want to do with a prime anyway and I don't want size and weight in a walkabout lens.
If it's bragging rights you're after, that 58mm f/.95 Z-mount Noct lens coming out in 2019 looks like a monster, but like the Canon 28-70mm, most of us will be lucky if we manage to put our hands on it just once in our lifetimes.