"Computer with 8 gigabytes of RAM is expensive!!!" is the actual story with the current mac pro.
So while I think it's fair to question why the base model Mac Pro exists, I understand the price given the (specific) hardware it contains. You're paying an Apple Tax on top, of course, but if you don't think macOS adds additional value you should be looking elsewhere.
I really think most of the people complaining about the Mac Pro's price want it to be something it's not. I understand the desire for a consumer-level, upgradable Mac desktop, but that's not what Apple set out to create with the Mac Pro.
You have to compare apples-to-workstations.
The Dell Precision 7920 I am wasting my company time on right now was more than $10k. Most PcMaStErRaCeRs would comment that they could throw together some aliexpress parts and "beat" it but my workflow won't... flow with less than 768GB of RAM and I can't guarantee (within comfortable margins) that my output is correct unless it is run on a Quadro RTX-- with 32GB of memory.
But yeah, a pee-cee can get more eff-pee-esses in Doom.
A firm that is processing several million dollars worth of data on a workstation doesn't really care, within reason, about the price of the workstation.
The cost of catering for some of the projects that these workstations will be working on will vastly exceed the price of the workstations, and you poop out the catering at the end of the day while the workstations keep on workstationing.
And if my Dell breaks? A guy will drive for over an hour to where I'm sitting and put a brand new one on my desk before the end of the business day, and he'll swap out the drives. Try that with stuff from pcpartpicker.
I don't know what applecare does for the Mac Pro, but if they start carrying them in stores I'm willing to bet you'll be able to walk in with a broken one and walk out with a fixed one.