I bought a special machine for Houdini and other CGI stuff when I realized how painfully expensive is my iMac 5K retina. This turned out to be very expensive and not usable monitor. The processor is already old and the graphic card is impossible to replace. To sum it up for the OP, Mac Pro is not worth investment. Not even in the big pipeline studios, I can't see how the 4K price just for the machine and expect to invest in the pro monitor another 4K (with the ergonomic stand it will be 5K). Realistically, you can get beautiful result for investing 5K with custom made machine which includes a 4K monitor. Mac asks you 9K for the arguably less impressive result. I am not sure who is the target for these new machines. Maybe some huge studios who need one or few machines with expensive monitors specialized for color grading and mastering. Other than that, I have no idea who should buy these overpriced machines. Word of advice - save your money. Sooner you get off the MacOS addiction, better for you, your projects, and your wallet. And this is coming from the current Mac user, I am still on Apple in all other aspects, my laptop, working machine for 2D stuff. But for CGI I think Pavel is absolutely right, so far Windows is the best bet, unfortunately.
I'll help you out a bit. YOU ARE NOT the target audience for this machine. I know that because you are comparing both the Mac Pro to PC's and the reference monitor to regular monitors.
When I saw this reference monitor for ONLY $5,000, I about lost my lunch. I couldn't believe how cheap it was and couldn't be more excited to finally get a comepetitive reference monitor to compete against what we have at the studio, which all cost at minimum $40,000. THAT is the league of reference monitors you are meant to compare this monitor to…NOT the 4k screens at Best Buy. You are NOT the target audience for this reference monitor.
As for the Mac Pro itself…it is a WORKSTATION CLASS system, and without question, the most powerful machine on earth. 8tb of internal SSD storage, 1.5tb of RAM, FOUR AMD Radeon Pro Vega GPUs, 2 on each Pro Vega II, connected via Apple’s proprietary Infinity Fabric Link connector inside Apple’s proprietary MPX box. And don't forget the eight PCIe slots and Thunderbolt 3 support. And we haven't even mentioned the 28 cores…
…and most importantly…don't forget this is ALL HAPPENING IN ONE WORKSTATION…
The bottom line is, this is the most powerful singular computer on earth upon it's release, and it is definitely NOT for you. You aren't the target audience. People who run racks in studios, render farms in the back room, indie artists who have $20k leftover from last year's haul and want to upgrade to the ultimate powerhouse system to take the pipeline to unparrarelled speeds…these are the target audience. I have had $17,000 stashed away for this machine for a year now from last year's earnings and I'm positive my first 4 projects in 2020 will pay for the machine…
This isn't a machine for a hobbyist. Just build a $5,000 PC if you're a hobbyist. This isn't a machine for gamers. That same $5,000 PC is going to run fortnite at 300fps with top settings and will be perfect for all your youtube videos. This machine is strictly for artists who make a living on high-end products. Commercials, Music Videos, Movies, Television, VFX, Sound Editing, Music Production, High End Photographic Manipulation, 3D Animation, 2k - 8k raw footage (of which you can run 6 streams of 8k raw on this machine)…THESE PEOPLE are the target audience.
But let's talk money and see if you financially line up via your work:
If $40/month—a fraction of a billable hour for many of the pros who will buy this box—is a meaningful amount of money, there’s absolutely no way the 2019 Mac Pro is in any way something you should be thinking about buying.
It's ego — people don't like hearing they may not be this level “pro”, being discovered like guys with big Pickups that don't haul anything. This machine is a bargain for network-connected workstations. And anyone thinking the monitor is too expensive — it's only because you don't need a reference monitor.