I want the 5DM4, but for me right now it makes no sense. I think it is an advanced camera, and would love to have it if I had the money, but I don't, and my 5DM3 remains an exceptional camera. My main photography "work" is as Chair for Photography & Media for our high school Band Boosters organization.
This is about tradeoffs. Nearly 4 years ago I got my 5DM3. Since getting it I've taken nearly 70K photos with it, high school sports and marching band mostly. (Fwiw, I never use continuous shooting.) There's some fashion photography in there, as well as various other genres. Much of what I shoot is action, low light situations. I shoot much at ISO 12800 and higher. Between the 5dM3 (and the RØDE Shotgun mic and DeadCat®) and the G16, I can shoot needed band videos at 1080p.
The 5DM4 does 4K video, which would be a plus, especially for making training videos, allowing me to crop the video in post and keep high resolution. I'll do 5 videos this season. After that, video is done as I typically don't do video. The M4 has native ISO to 32000; the M3 goes to 25600. Even allowing for lower noise with the Digic 6+ and improved sensor, I'm not getting much more for my money. Images are larger, and that means my 14TB system (yes, that's right, as I have multiple external drives) would need to be expanded.
One of my metrics for evaluating equipment is looking at what I want to do that I cannot with my current suite of equipment. I'm still pushing my 5DM3 and myself, and haven't reached limits where I've said, "My camera is limiting me. I need feature X to really get the photo I want."
I'm not a pro, though I aspire to be one or at least take the craft and art as a pro. I'm equally happy shooting with a Canon ELPH as I am the 5DM3. I've gotten some interesting action shots with my Elph 330. It's a fun little camera, and it challenges me to make the best with a limited camera.
Bottom line is that I'm one of those who would love the M4, but it doesn't make sense for me to get it right now.